Tag Archives: physical science

Science: More Electricity

Hey, I finally updated the list of posts on the science page which is on bar above.  In case anyone was curious.

We spent a second week exploring electricity, though without the same depth as the first go around.  For this week, we looked at more complicated circuits.  We started by just looking at the light switches and I showed them the electrical box in the basement, which was more exciting than I would have imagined.  Then, we dove into real experiments, drawing again on the book Power Up that we used the week before.

We started with lots of extra “wires.”  Just like last week, these were just strips of foil lined with tape and folded over.  I put down a line on each end of the table in tape.  On one side, I put the battery and on the other, I put the little 2.4 volt bulb.  I told them to make the bulb light without letting the bulb or the battery cross the lines.  There was just enough foil wire to make it work and they got there after some experimenting.

Next, I left the bulb and the battery, but I took away more than half the wire and told them they had to do it again.  This time, they could go find anything they wanted in the house to get it to work, except more foil wire.  They had to get really creative.  They also had to remember how to test and see if something is a conductor or insulator.

They had to get pretty creative to make it work.  They started with little chains of paper clips and then moved to scissors and finally raided the kitchen for giant spatulas and the like.  I had to show them to some tape to hold their crazy circuit together and we talked a little about insulation around wires.

After they had gotten it to light, we talked a little about how electricity is usually generated.  The Magic School Bus book about this topic was especially useful because it covers generators.  Then, we undertook a complicated project: building a tiny generator.  You can see the plans for this project here.  Essentially you use wire and wrap it around a big magnet, then spin it and make a teeny-tiny bulb light up.  I cut the cardboard and did more than one Radio Shack trip to get the materials (which weren’t that expensive).  Below, you can see them winding the wire.

Well, cut to the chase.  We couldn’t make it work.  Grrr!  And then I was called out of town so I couldn’t really fiddle with it myself over the next few days to make it go either and I haven’t gotten back to it.  I feel like it was a really worthwhile thing to try and the kids were really into it.  It just didn’t work for us.  I’ll let you all know if we update it what the trick was.  I felt like I had followed the directions pretty well.  I guess if we’re ever stranded without electricity in some post-apocalyptic world, then I will not be the person building the generator.

Science: Electricity

There were so many good ideas of ways to explore energy, that I knew immediately this would be a two week topic.  This week for our activities we focused mostly on static electricity as well as began looking at current energy through batteries.

But, as always, we started by reading books and watching videos.  There’s no shortage of resources for electricity, so let’s get to it.


All of our traditional sources served us pretty well here.  The Magic School Bus offers the classic book The Magic School Bus and the Electric Field Trip, which does not have a corresponding episode.  Let’s Read and Find Out gives us Switch On, Switch Off which is a perfectly good option.  There are many other series we found as well.  However, the best title by far was the book Flick a Switch: How Electricity Gets to Your Home by Barbara Seuling.  This might also be a good time to revisit the Loreen Leedy book we loved so much, The Shocking Truth About Energy, since it focused a great deal on how energy eventually ends up as electricity.

Videos also gives us a lot of options.  The Magic School Bus has an episode about electricity called “The Magic School Bus Gets Charged.”  Oddly, it revolves around Valentine’s Day (it plays on the idea of “attraction” – get it?).  Bill Nye brings us two different topics, electricity and static electricity.  Since we were working with batteries this week, we also watched a couple of videos about batteries.  Below, you can see the How It’s Made episode about batteries.  Also, we found this cute school video about how batteries work.  The terminology was way over the kids’ heads, but they still thought it was cute.  I feel like school video projects are really high schoolers’ gift to Youtube.  We adored that one about Lego Newton.  Sometimes I watch them and think, “Maybe one day my kids will make science videos with Legos for Youtube!”  Oh, but I digress.  Here’s another video, this one about the iconic story about Benjamin Franklin’s famous experiment with electricity.

Now for the experiment books.  We used several good experiments from The Science Book of Electricity by Neil Ardley.  Bernie Zubrowski also gave us a solid entry with Buzzers and Blinkers, though most of it was above the kids’ heads this go around.  We had several other electricity books out, but the one I enjoyed the most by far was the book Power Up by Sandra Markle.  This book had the best, simplest ways for kids to play with electricity and batteries.  As you’ll see below, all we needed to get started was a battery, a flashlight bulb and some tin foil.  It also put things into a sort of puzzle context and invited kids to play with the concepts more than most of the other books, which were more formulaic experiments.  I wasn’t familiar with the author, but she has a newish blog about writing nonfiction for kids that I thought was actually pretty good.

We began with our notebooks and reviewed a bunch of ideas about electricity.  We talked about how it’s a form of energy that can be easily turned into other forms of energy.  We talked a little about atoms charges.  Atoms is something that the kids are vaguely familiar with from a number of sources, but we haven’t officially covered it and it’s not solid in their minds really.  I’m hoping I didn’t oversimplify too much when I talked about how parts of the atoms “get excited” and end up moving around, which leads to electrical energy.  Perhaps we’ll revisit this topic next year after we have a firmer understanding of atoms.  Finally, the kids drew something that uses electricity.  Three of them drew TV sets and one drew a vacuum cleaner.  Hm.

Next, we did three simple experiments with balloons and static energy.  I began by letting the kids show me what they knew about static and balloons by just giving them the balloons.  With no instruction, they all rubbed them on their heads and asked if their hair was standing up.  It was.

Next I showed them a few tricks.  We rubbed the balloons on the wool rug and a wool sweater to get a better charge then used them to bend the water coming from the tap in the kitchen.  It’s a slight bend, but definitely there.  Here’s a version of that using a comb.  We also tried to get two balloons to hang together, but discovered that when they are both charged, they resist each other.  That experiment is here but I’ll add one trick to it, which is that if you put a piece of paper in between the balloons, then they’ll switch and attract each other.  Finally, we did something a bit like this experiment where we used the balloons to pick up small scraps of paper.  I made it into a small contest where the kids had to see how many they could each get with their balloons.

All of that led to a nice discussion of positive and negative charges.  We talked about attracting and repelling.  I handed them each a battery and let them look at it.  We talked a little about how we were about to experiment with current energy, but that current energy can be pretty powerful.  We talked about safety with household electricity and with batteries before going to experiment with the batteries.

I gave them the aluminum foil strip (which was backed with tape and folded to help it not easily rip), the battery and the flashlight bulb, which was a 2.4 volt bulb.  You can buy one at Radio Shack if all your flashlights are LED (which ours almost all were!).  I told them to try to make the light bulb come on without anything else.

This is where BalletBoy’s Snap Circuits training came in handy.  Snap Circuits is this great toy that lets kids explore circuits and electricity.  I got the kids Snap Circuits Jr. back in the fall as one of our beginning of the school year things.  The junior level lays out every project very clearly so kids are basically just following directions.  Any kid who can build a basic Lego set can do it (so don’t mind the age 8 and up label, I suspect many kids could begin to appreciate this at 5 or even 4 if they were good with putting things together).  However, over time, kids begin to figure out what works.  BalletBoy likes puzzles so he loves this one.  You can upgrade the junior kit to a regular one by purchasing a small kit.  There are also millions of different add ons you can get for it – motion detectors, rovers, alternative energy stuff, and more.  It’s a great product.

But getting back to our less plastic and non-snapping circuit, BalletBoy immediately recognized that, “It’s got to be a circle!”  The problem was figuring out how to make the circle work.  They all fiddled with it for a while and they almost got it, but I finally showed them how to wrap the foil “wire” around the metal base of the bulb then touch the bottom of the bulb to the top of the battery while keeping the other end of the foil touching the other side of the battery.

After that, the kids experimented with different ways to attach it.  For example, they discovered that is does work if you turn the battery around.  I also gave them more batteries and let them try attaching them all together.  They immediately got that the two sides of the batteries had to touch with opposite ends (positive to negative) and then when I made the connection to the balloons repelling each other, they seemed to get it.

Finally, I showed them how a paperclip can extend the circuit by setting in in between the bulb and the battery (keeping the foil wire touching the end of the battery and wrapped around the base of the bulb).  However other things, like paper, would make the battery stop working.  I sent each kid out to find three things they though would insulate and three things they thought would conduct.  The stuff they found was awesome.  They were much better at picking insulators.  Mushroom probably had the funniest assortment.  He wanted to test chocolate, an Easter Peep, and some honey!  Other kids had Legos, a balloon, and a number of other things.  The conductors were also interesting.  One of our friends thought surely glass would be a conductor.  Mushroom expected rock to work.  BalletBoy brought in a corn holder and we discovered that it would conduct from one end to the other (meaning the metal must be one piece encased inside the plastic).  All the kids were shocked when the stainless steel dinnerware didn’t conduct electricity.  I realize now I should have taken out some silver.  They may have emerged with the idea that forks just don’t do it!  We recorded all these observations in the journals, which worked really well.  I like when our journals can be used for recording observations like that instead of just notes and illustrations.

Science: Sound

Sorry I didn’t get around to writing up science last week.  The reason was that I spent most of the time (or, at least, it felt like I spent most of the time) yelling at the kids, and not because the topic was sound and I wanted to teach them about raising your decibels.  The afternoon after science, it felt like it had been a colossal failure and my throat was a bit hoarse.

Well, turns out I was sick, or rather, pre-sick.  A couple of days later, the flu hit me like a ton of bricks, as they say.  Later on, I made a small list of all the stuff we had actually done that day and realized it hadn’t been a colossal failure.  It wasn’t a perfect science day, but it wasn’t too bad either.  Still, in the intervening time, my partner in science (the mother of the other two lads who take their science lessons with us), and I had a little talk, so next week we’re shaking some things up.  More on that next week, I hope.

But first let’s start off with some resources about sound.  All our favorites have good stuff about the topic of sound.  The Let’s Read and Find Out title, Sounds All Around by Wendy Pfeffer is perfectly fine.  “The Magic School Bus Inside the Haunted House” is also a good introduction to the topic.  Of course, the Bill Nye episode “Sound” didn’t let us down.  For additional videos, we found a couple of good options.  I especially liked this very old classic filmstrip video about sound, though it’s a bit on the long side.  The kids really liked this cartoon, which is incredibly short (you can find a link to the second part afterward though).  We also enjoyed this segment from NASA Connect, which has several short videos like it on various topics.

There are more experiments for kids with sound than you can imagine.  We had five books of just experiments out from the library, not to mention all the various experiments I found on the internet.  Sound is obviously a topic that can be easily explored in multiple ways by kids.  It can’t all fit into one day of experiments.  I tried to organize some of my thinking about ways to begin to explore sound.

The first concept to explore was that sound is a wave or a vibration.  We began by putting out hands to our throats and feeling that vibration.  The kids made different noises.  I had them slide their voices and they made their own noises and described what they felt.  Next, we tapped and banged various drums with paperclips on them to see how the vibrations on top of the drum can move something with very little mass like a paperclip, even when it seems like there’s no movement.  We plucked various rubber bands as well and watched them vibrate.  Finally, I had the kids make paper bangers.  You can find instructions for how to do it here.  I thought this was brilliant.  The origami was pretty simple, but the kids struggled to make theirs bang.  I could do it easily, but they had trouble flicking them just right.  Supposedly, these are much easier with newsprint, so I recommend doing it with the largest, lightest paper you can find.

For the final experiment with sound vibrations, we made a small sound cannon.  We used a coffee can and punched out a hold the size of a tennis ball in the metal bottom.  You can find alternate directions here if you don’t have a coffee can.  We hung small strips of tissue paper from the mantle and took turns firing our cannon to see from how far away we could make the tissue sway.  You can see BalletBoy trying it below.

The next idea, I wanted to explore was how sound waves can bounce.  We made megaphones from stiff cardboard and played around with those for awhile.  Then the kids went around trying to make their sounds bounce even more by speaking them against different surfaces, such as walls, glass, wood, and metal.  We talked about how these are echoes.

I wanted to follow up on that concept and explore how different materials conduct sound waves differently, but this was the point at which the afternoon seemed to be falling apart, so we didn’t really get there.  Instead, I decided to finish up with what I hoped would be the two most exciting activities.  First, we made a real, honest to goodness tin can phone.  It worked quite well – so well that I jumped back a little when I first heard BalletBoy’s voice through it.  We used nice kite string, which I suspect was an important component.  If you know nothing about tin can phones, here’s a simple set of instructions.

Finally, we did a version of this experiment, where you try to demonstrate that light (what we see) moves faster than sound (what we hear).  Mushroom stood more than halfway down the block with a balloon full of flour.  It decidedly did not work.  We saw the flour explode and heard the pop of the balloon nearly simultaneously.  I’m still working out how to counter the misconception that arose from that.


Science: Waves

Since we started a new science unit, I thought I’d ditch the numbering of the weeks.  In case you didn’t notice, I messed it up anyway.  This new unit will cover light, sound, and electricity.  Because understanding energy is such a big part of these topics, it’s strange to me that it’s a totally different section in The Usborne Science Encyclopedia, but whatever.  The kids liked that it’s a new unit.

WavesFirst of all, let me clarify by explaining that “waves” means ocean waves, sound waves, radio waves, and all the other electromagnetic waves.  This section simply introduces wave behavior.  We found some good resources.  There were several good book offerings about tsunamis at the library which we read, probably in part because of the tragic tsunami of a few years ago.  However, the best book we found was Waves: The Electromagnetic Universe by Gloria Skurzynski, which covered electromagnetic waves in a lot of detail, but not too much for the kids.  There were many fine books about sound waves, but we’re saving those for next week.  The Bill Nye the Science Guy episode about waves is excellent.  Here’s the, as always hilarious, music video from the episode:

We began with our notebooks by drawing simple waves and labeling the crest, trough and wavelength.  We talked about different kinds of waves and the kids knew that waves could be in the ocean or the water, that sound was waves and that some waves had, as Mushroom put it, “something to do with something like electricity.”

Product DetailsThen, drawing from the book Making Waves: Finding Out About Rhythmic Motion, we began a bunch of exploratory experiments.  This book was so excellent, that I went to see if there were others in the series, which is called the Boston Children’s Museum Activity Books.  I was delighted to find that there were, even in my library system (though I’m scratching my head at why I haven’t seen them before).  While we didn’t build some of the elaborate things the book called for, such as a wave generator or the clear wave experiment box, it was exactly the sort of book I want about science topics.  Instead of laying out just a few “cool” experiments, it suggested open-ended ways to explore the topic with different materials.

We began by playing with making waves using our fingers and various toys.  We started with a very shallow pan of water.  We added tiny floating confetti to see if it helped us observe the motion of the water.  Next, we went to the big, clear containers of water.  We did some of the same explorations, then added some food coloring to help us see the waves from the side.  In addition to just identifying the crests, trough and wavelengths, the kids made some good discoveries about how the waves move, for example if you start two waves in different directions.

In order to illustrate the idea that the water in the wave may move up and down but doesn’t change position, we moved to the living room to knock over rows of dominoes and knock a row of marbles so that the energy transfered through the marbles and sent the final marble rolling.  The kids understood this idea immediately, which made me feel good about all the learning we did about energy earlier in the year.

Next, we explored waves with rope, string and sheets.  We tried to see how many wavelengths we could get and how big or small we could make them.  The kids enjoyed this very much, as you can see below.

Finally, we looked at the electromagnetic spectrum a little bit.  We added an illustration of the different waves in the spectrum to our notebooks.  Then, the kids ran all over the house to find different things to show off that use the electromagnetic spectrum.  They found some obvious things, such as the microwave, the TV and the clock radio.  Then they found a couple things I hadn’t though about, such as the remote control, which I had to look up to be sure I had right (it uses infrared light).

Overall, I was happy with this introduction to the idea of waves in different forms, so I’m hoping they remember some of the concepts as we tackle sound and light in the next few weeks.

Science Week 13: Engines and Cars

On the one hand, I didn’t want to skip engines.  On the other hand, there was less in the way of actual experiments to do for this particular topic.  There’s just not so much you can get first graders to do with engines and cars.  Also, apologies for the lack of pictures this week.

Most disappointingly, all our usual resources failed us on this topic.  There’s no Bill Nye, Magic School Bus or Let’s Read and Find Out title about engines.  Since engines are such an omnipresent fact of life in our world, I found this a little surprising.  The best book I found on the topic was the book Car Science by Richard Hammond.  Much of the information was above the kids’ level, but glossy pictures always helps.  We also enjoyed a simple easy reader called Cars by Nancy Smiler Levinson, which told a brief history of the automobile.

Luckily, the online video resources for this topic were much more plentiful.  We found a whole bunch of great options.  The best video was probably the one from How Stuff Works that I’m embedding below, which used the simplicity of a potato canon to introduce engines.  Potato canons are apparently very funny to children, so this video went over very well.

We also enjoyed the video from Newton’s Apple, which is here.  You can also find some other good resources and activities there.  This video about the history of the automobile was also a good summary.  Finally, we enjoyed this demo of an old Watt Steam Engine.

We began by talking about what an engine is and what combustion is and writing down the definitions in our notebooks.  We brainstormed all the different types of fuel we could think of and I reminded the kids what we had learned about energy earlier in the year.  I was thrilled that they remembered that the energy in coal or wood originally came from the sun because they were originally plants making their own food.  Kudos to the kids for understanding energy chains.  To demonstrate fuels, I set a whole bunch of things we had around the house on fire.  We burned a candle, a small oil lamp, some paper, some wood, and I also demonstrated a lighter for them.  BalletBoy, who has apparently developed a recent phobia that I’m going to burn down the house, ran to take refuge in the kitchen.

I started the stove and we talked about natural gas a little bit.  We boiled a pot of water with the lid on and watched the steam escape from the pot and rattle the lid.  This worked pretty well to get across the idea that burning a fuel can start a chain that leads to movement.

Next, we talked about engines in our world and the kids cut out pictures of things that run on engines from magazines for their notebooks.  BalletBoy found a cool picture of a giant digging machine that makes tunnels in an old National Geographic. We talked a little about why engines are hurting our environment.  Finally, we went out and looked at the car and checked out what it looks like under the hood.

However, the most exciting part of the day was when we pulled out the Putt Putt Boats.  If you’ve seen the wonderful movie Ponyo then you’ll know what these are.  They’re tiny steam engines.  The boat sucks in the water, heats it with a tiny oil lamp or candle and then propels itself forward.  Despite the frigid weather, we set up a kiddie pool at our friends’ house and sailed the tiny boats.  As they go, they go putt-putt-putt-putt-putt, which is how they got their name.  The cold made it a short demo, but I’d like to take these out in the spring again and get them going on some real water, maybe in Rock Creek.  If you’re interested in learning more about Putt Putt Boats or buying one, you can find information here.

Science Review and The Box of Science

We absolutely did science this week, but I’m swamped with Tempest rehearsal stuff and life in general, so I thought I’d do a couple of other things instead of posting about our week.

First of all, this lesson wraps up the first section we covered in our spine The Usborne Science Encyclopedia.  This unit took up half the year and covered the section called “Energy, Forces and Motion.”  In case you’re interested, here’s the links below to all the sections and how we covered them:

Energy Parts 1 and 2
Heat Parts 1 and 2
Forces and Motion Parts 1 and 2
Simple Machines
Sinking and Floating

Engines (to be posted next week!)

Looking back, I feel pretty good about how we covered these topics.  Obviously, there are things I see that we could have done better (things other than just me realizing that I accidentally misnumbered the science weeks…  oopsie).  But overall, it’s good.  Coming up next is our second half of the year unit: “Light, Sound and Electricity.”

And just so you don’t feel like this post was all links to other posts (don’t you hate that?) I thought I would share a little about our science organization.  At the start of the year, I looked at a lot of the experiments I wanted to do with these topics and began gathering the materials we would need into a single box so that I wouldn’t need to think about things like, “Hey, do we have any ping pong balls?” every week.  I couldn’t keep absolutely everything on hand, but I’m so glad I did this.  And having see how many of these common household items are used over and over again in experiments, such as the ones in the Janice VanCleave books, I want to keep up our Box of Science so that it can continue to be a one stop spot for experiments.  I had a few things in there that were specific to our units, such as the wacky whirlers I mentioned last week and the putt putt boats that I’ll tell you all about next week.  However, the vast majority of stuff was just common items that I might have forgotten to have around if not for two elementary school science students.

Here’s what we’ve got:

  • balloons (regular and water balloon size)
  • rubber bands
  • magnets
  • one large pickle jar and one small baby food jar
  • straws
  • marbles
  • ping pong balls
  • beach ball
  • magnifying glasses
  • string
  • modeling clay
  • two liter plastic bottle
  • paper clips
  • duck tape and Scotch tape
  • scraps of cardboard
  • tin foil
  • baking soda
  • vinegar

Wow.  The Box of Science is a bit of a mess now that the unit is over.  Must refresh and get it ready for our next unit.

Science Week 10 and 11: Floating and Sinking and Flying

I got seriously behind on science, in case you didn’t realize so prepare yourself for a mega-sized Science Friday post.  We do our science afternoon once a week with another family and the holidays as well as a million other things conspired to make us miss it for a long time.  The kids and I kept watching videos, reading books and exploring science informally, not to mention with one of our co-op groups, which has been pretty science focused, but it’s nice to get back to a proper sequence.

First up, our last class before the holidays was about floating and sinking.  As I somehow put off posting about it for so long, I don’t have much to say.  The Bill Nye the Science Guy episode about buoyancy is a pretty good one.  There’s a clip here.  There’s also a Magic School Bus episode about floating and sinking which isn’t bad.  We took out a number of books about ships, but none were especial standouts.  We happen to own the book shown here, which is a fun pop up book about ships that the kids especially enjoyed.  It’s nothing deep, but there wasn’t anything especially insightful at the library on ships either.

Floating and sinking meant a bunch of of activities trying to float and sink various items in a big tub of water.  I was pleased by how focused on scientific discovery we were that week.  Both our activities allowed the kids to test and discover.  First, we played an extended game of “Will It Float?”  The kids ran all over the house and picked out items to test.  They had to find two things they predicted would float and two things they predicted would not.  Second, I gave each of the kids a lump of modeling clay and challenged them to make it float.  This is a pretty classic experiment.  As a ball, the clay sinks, but if you mold it just right into a boat or bowl shape, then it will float easily.  You can see them working on it below.  To finish us off, I did this experiment where you float and then sink an orange by peeling it.  The discussion about why this works was a good one.

This week, we picked up again with the topic of flying.  This was an excellent one with lots of good book and video resources.  I probably won’t even begin to list all the excellent possible places you can look to learn about airplanes and flight, but I’ll try to give a sample.

First up, the Let’s Read and Find Out book How People Learned to Fly by Fran Hodgkins was excellent.  It was part history lesson and part aerodynamics.  We had a number of other books about airplanes, but we especially enjoyed The Airplane Book by Cheryl Walsh Bellville.  It was a little older so the “new” planes it talked about weren’t that new, but this book gave a succinct history of flight with photographs and explanations of the technological innovations through the history of flight.  It explained not only how older planes like the Wright Brothers’ flyer worked but also how jets and newer planes are different.  Plus, for any kids out there who are focused on specific models (that’s not Mushroom and BalletBoy, who couldn’t care less), this book gave a lot of specifics about different airplanes.

For videos, both The Magic School Bus episode about flight and the Bill Nye the Science Guy were excellent.  While the highlight of the Bill Nye episode for me personally is probably that the video parody is “Smells like Air Pressure” (no, really, it’s hilarious!), as always Bill summarizes the main points really well in this one.  We also found some great quickie Youtube videos, such as this one about how airplanes fly.  However, the best loved video for the kids was probably this one that I’m embedding below, which showed early, failed flight attempts then ended with footage of the Wright Brothers’ flyer at work.  It was funny, but we also talked a little about why these ideas didn’t work and why people initially thought they would.

Many of our activities were inspired by the Magic School Bus science kit Soaring Into Flight which we owned and did well over a year ago when it was fun, but difficult for Mushroom and BalletBoy to understand the concepts behind.  I kept the experiment booklet and drew from it for these activities.

We began, as we usually do, with our science journals.  The kids drew images of things that fly and showed them off to each other.  They also put down that air pressure is what allows airplanes to fly.  Then we highlighted four forces at work when an airplane flies: lift, thrust, drag and gravity.

Since air pressure isn’t something we can see, we explored it in a couple of ways.  First, we drank from juice boxes and explored how we could effect the air pressure in the juice box.  Next, using two ping pong balls attached to the table with string, we explored how blowing between the balls creates a low pressure area since fast moving air has lower pressure.  The balls move together if you blow exactly between them.  Even with a straw, BalletBoy had trouble aiming his air, as you can see below.

Next up, we explored drag with some classic parachute drops.  The kids each picked a different toy and we dropped all of them from the top of a tall step stool.  The Lego minifig worked much better than the stuffed animal Mushroom chose, by the way, so we talked a little about why that was.

For the next activities, we explored thrust.  First, we had a paper airplane contest.  The kids chose different models or made their own and we tested them to see which plane went the farthest.  We also went back to basics and talked a little about energy transfer and how these planes got their energy from us throwing them.  Then, we did an experiment that we did when we were exploring forces.  I strung up a long string with a straw on it through the house.  Then I blew up a balloon and we taped it to the straw and let the force of the air propel it forward.  The picture isn’t that great, but you can see the kids are trying to race the balloon through the dining room to the living room.  They wanted to do this activity half a dozen times, if I recall.

Our final experiments dealt with lift.  I gave each kid what I consider to be one of the best 75 cent toys money can buy: the wacky whirler.  I put a picture of it at the left so you can see it clearly.  You just twist, let go, and up it flies.   The kids played with them for about an hour outside.  Thank goodness it was a warmish day for January.  Below, you can see Mushroom watching his intensively, perhaps in the hope that it not get stuck in the neighbor’s yard and have to be retrieved by climbing over the fence like BalletBoy’s did!  (Shh…  no one tell the neighbors!)

The Wright BrothersYou might think that was it, but we had the pleasure of going to the Smithsonian Air and Space Museum the following day, where we checked out the Wright Brothers’ exhibit as well as many of the old planes we had read about in the books.  Then, we saw a Discovery Theater puppet show about the life of the Wright Brothers.  It was a musical where they made the kids get up and dance.  Usually, that’s not my kind of thing, but this was extra well done.  I don’t think I’ve ever had a performance and museum dovetail this nicely with a lesson, so I felt like this made for an auspicious start back for science.

Science Week 9: Pressure

I’ve got that David Bowie and Queen song stuck in my head this week…  “Under pressure…  Pushing down on me…”

Okay, now that we had a musical segway, onto pressure.  We began, as we usually do, by copying the definition of pressure into our science journals.  Then, to demonstrate right on the notebook, we each picked a colored pencil and experimented with different pressures.  You can see Mushroom at it below.  We also just tried putting pressure on different things and talking about the things that put pressure on us.

Then, we headed outside to hammer in some nails.  First, we tried hammering them in upside down to show how a sharper point can be influenced by pressure.

When we came inside, I showed them this video from Youtube where a teacher demonstrates laying on a bed of nails and having a cement block broken over another bed of nails on his chest.  The kids were as fascinated and appalled as the students in the video.  We used it to talk about how the pressure was spread out.  BalletBoy and Mushroom have actually lain on a bed of nails before at the Maryland Science Center, where they have a machine that allows the nails to rise slowly to ensure that the pressure gets distributed evenly.

Our next series of experiments came mostly from this website.  I’ve used some of their experiments before for other topics.  We tried the experiment with the lemon diver, where you make a little slice of lemon dive down by changing the air pressure, however, we couldn’t get a balloon to fit over the lid of the jar properly.  Doing the marshmallow faces also fizzled out.  I’m pretty sure the seal on the jar was airtight.  However, I think I might have needed to buy the really nice marshmallows to make it work.  I think the cheap ones weren’t puffy (and therefore air-filled) enough.

However, we did a number of variations on this experiment where you keep things dry by using air pressure under the water.  Even though it was simple, the kids were enthralled that you could hold air under the water.  Also successful was when I gave each kid a little bowl and a piece of cardboard.  When you fill the cup with water, put the cardboard on it and make a snug seal, you can flip it over and remove your hand.  The pressure will keep the cardboard in place.

To finish off our experiments with water, we put some holes into a plastic bottle and watched how the greater pressure at the bottom pushes the water out farther.  This was a good jumping off point to talk about how the changing air pressure can make our ears pop and how if you dive to the bottom of a deep swimming pool you can really feel the pressure.

To finish us off, I let the kids all try out the air pressure gauge for the tires on the car.  One tire was a little low, so we stopped and filled it on the way to take our science pals home.  I love it when science and errands come together!

Science Week 6: More Forces and Motion

We dipped into forces and motion for a second week of experiments and readings.  This week, we hit the Bill Nye episode about momentum and read a couple of the nonfiction section’s lesser offerings on the subject, including the book Forces and Motion: Questions and Answers by Catherine A. Welch.  This is one of those books that only asks you really obvious questions with simple, straightforward answers.  I guess I’m glad we had extra books to flesh out our pile, but I wish more science books for younger readers would treat their readers with more respect.

But on to the fun stuff.  We began by reviewing Newton’s three laws in the simplest terms.  For their science journals this week, the kids drew an illustration about each law.  Here are BalletBoy’s below.  The first law shows an apple falling (until stopped by Newton’s head) and an apple staying still.  The second picture shows someone trying to lift a big pile of books versus a single book.  The third picture shows the card houses we made last week – in other words, two forces balanced against each other.

Then we did experiments to think about each law.  For the first law, we talked about inertia again and pulled a piece of paper from below a cup full of water.  In other words, more magic.  We did a lot of these tricks last week.  This time, we moved on after that one.  Taking that same cup of water, I put a layer of oil on top then put four drops of food coloring.  We took turns slowly spinning the cup on the table so you could see that the liquid resisted moving.  In other words, it had inertia.

Staying with the liquid theme, I showed the kids two eggs.  One would spin easily.  The other resisted spinning, but once you got it going, it was harder to stop.  The one that spun easily could be stopped with a tap, but the other one kept going even after you stopped it with a light tap.  The kids had various ideas about this.  We ended up weighing the eggs on the balance to show that the difference in their weights was negligible.  Finally, I let them crack open the eggs.  The easy spinner was hard-boiled.  The one that didn’t like to spin (and then didn’t want to stop) was a raw egg.  We talked about what made that one different.  Overall, I think this was one of the most successful experiments we’ve done so far.  The kids loved trying to figure out the mystery and had many great (if not correct) ideas about what made the eggs act so differently.

Next, we continued with liquids by exploring centrifugal forces.  The kids made little buckets out of paper cups and string.  Then, they made quite a mess in the kitchen.

For the second law, we watched another Eureka video then did exactly what they talked about in the video.  We threw a heavy ball and a light ball.  I think, at least at this level, Newton’s Second Law may be the most intuitive.  The kids all know that heavy things are hard to move.  After all, they’re tiny and the rest of the world is huge.

For the third law, we did a classic experiment with a balloon taped to a straw and threaded on a string.  I tied the string to the easel on one end of the living room and the abacus on the other.  Of course, when you let the inflated balloon go, the force pushes it across the room.  This one delighted the kids.

So did playing with a gyroscope at the end of our experiment time.  The gyroscope did what they do and spun on the table.  We also watched an excerpt from the show Beakman’s World about gyroscopes.  The kids like that show much more than I do.  I find Beakman a little…  annoying.  Somehow when Bill Nye is manic on screen, it’s endearing, but when Beakman is, it’s just grating.  But hey, whatever works, right?

Science Week 5: Forces and Motion

And we’re back with forces and motion for science this week!  There are so many different ways to approach this topic.  We began, as we always do, with a pile of books.  The highlight was, as always, the Let’s Read and Find Out title, Forces Make Things Move by Kimberly Bradley.

However, we had another excellent title with the DK title Can You Feel the Force? by Richard Hammond.  That one began with a joke about THE force from Star Wars which really made the kids smile.  Ah, it’s the simple things that hook them, isn’t it?

After all that, I decided to focus on a couple of things.  We introduced Isaac Newton and his three laws.  Then we looked at the concepts of equilibrium and inertia (aka, the first law).  We’ll probably keep exploring those ideas in the next week or two, as well as adding new concepts.

The kids began by looking for ways to use force around the house.  I had each kid find a push and a pull they could demonstrate to the rest of us.  In the saga of how I’m continuing to figure out great ways to use our science journals, I snapped a quick picture of the kids demonstrating their pushes and pulls then printed them and taped them in the journals where they labeled them.  It worked very well.  Below is Mushroom showing us a push with the wheelbarrow.

And there he is pulling the string for the blinds.

Next we tried an experiment from the book Science Experiments with Forces by Sally Nankivell-Ashton.  We put things of various weights into a small box with a rubber band attached to measure how far the rubber band had to pull.  The measurement aspect was fun and it was nice to have a table to put into our science journals.

To introduce Newton’s laws, we turned to a video.  This was a very video intensive week.  Some of our videos are embedded below, so I hope you can click and enjoy the miracles of Youtube.  Here’s the first one, a Lego Sir Isaac Newton.  I can only hope my kids’ legomation gets as awesome as this kid’s.

And in case you just need a Bill Nye fix, here’s the parody song from the episode we watched.

To think about some of the concepts in Newton’s laws, we first started to explore equilibrium.  We used the balance that usually gets used for math to show off the idea of forces being equal.  Then we built card towers.  Next we had an excellent tug-of-war in the basement.  The kids tried some arm wrestling at the table.

Finally, we repeated the experiment BalletBoy got to demonstrate at the science show at Discovery Theater a couple weeks ago by hovering a ping pong ball with a hairdryer.  The kids loved it.  There’s BalletBoy showing them how it’s done.

Next, we began thinking about inertia by watching yet another short video, this time from the old Canadian show Eureka.  If you’ve never seen this show, it’s dated, but very cool and all available online in multiple locations.  This show has an odd feature in that it spends a full minute and a half talking about the other episodes, which is sort of off-putting for a 4 minute short.  Start your viewing at about 1:25 to see the actual show.

To demonstrate inertia, we did the trick where you pull a card from under a coin and a cloth from under a bottle.  The kids loved practicing it.  Then (and no one freak out) when we next got in the car, I demonstrated inertia by starting and stopping more abruptly than usual in the empty alleyway to let the kids feel their bodies go back and forth.  Two of the passengers thought this was great fun.  The other two clearly perceived that I was going to get them killed if I drove that way on the actual road and warned me never to do it again.  Such responsible youngsters.