Flying apples, flour, and racing in circles

Newton's second law is best summed up with the formula F=ma or force equals mass times acceleration.  It seems like it should take a lot of math to explain newton's 2nd law.  But in fact, it takes a marshmallow and a golf ball. :)  Let me explain.

Gravity is always our go-to force to study, since we can easily see it in every day situations.  When the apple falls onto the knife, it de-celerates because of the addition of friction, which changes the downward force until it finally comes to a stop.  This demo left the kids a bit confused, so we looked into something a bit more fun . . . and messy. :)

We filled a container with flour (sand would have been less messy, but I didn't have any on hand). Hulk held up a golf ball, and Goblin held a marshmallow.  Then, they dropped them into the flour. 

Then we measured how deep the holes made by each object went into the pan.  Since they had different masses (golf balls are much heavier than marshmallows), we can see the difference in force at which they hit the ground based on the difference in the impacts (the depth of the hole they made).

Since the boys were covered in flour, I made them go outside to shake it all off, which I think was everyone's favorite part of school for the day. Science should always be a little bit messy and a lot of fun.

--Little Miss Crazy

Chains of Energy

A subject I intended to cover over a week or so ended up being so much fun that we took two full weeks plus a few fun side tracks before we finished it.

The law of conservation of energy states that energy can not be created or destroyed.  Instead, energy transfers and changes forms: light, sound, heat, mechanical, chemical, etc.

First, we needed to establish that energy can be transferred from one object to another.  The easiest way to do that is to bounce two balls one on top of the other.  The energy from the bottom ball is transferred into the upper ball when they hit the ground, causing the top ball to fly much farther than it ever would have on its own.  Such a genius simple idea.  I would love to take credit, but as usual, I spotted this gem on E is for Explore!.  They just have a great way of making these ideas so simple.

We illustrated the idea of energy moving from one thing to another over and over again (making energy chains) using dominoes (technically, these pieces are from Colorfall, making them much more colorful and fun than ordinary dominoes). The kiddoes kept building paths and knocking them over for a long while.

Then, the important twist: energy can also change forms as it transfers.  We pulled out our old friends the Snap Circuits to demonstrate this concept. Our Snap Circuits Light kit allowed us to make our energy change form numerous times. We started with chemical energy in the battery, which changed to electrical energy running through the circuits, which became light energy with bulbs and fiber optic wire, which then moved across the room and turned into sound energy through the speaker.

We did some other demonstrations of energy changing forms, but our Snap Circuits certainly won the day and illustrated the concept perfectly.

--Little Miss Crazy

Solar Rover

After our overview of energy, we started discussing types of energy, and during one of our mostly-off weeks, I snatched up a kit, and the kiddoes got to make a solar rover.  During the construction, we got to talk a bit about solar energy: how we see it used day to day in people, plants, etc.  And of course this project brought up the idea of using it as an alternative fuel to power items, which is a pretty new concept for them.

They really only got to build the vehicle portion, since the solar panels were pretty much ready to go.  I connected the wires for them the first time, but when they got tugged, the kiddoes reconnected them themselves after folding down the panels to keep the sun out.

Ta da!  Complete!

Whoops-- not quite complete.  The kiddoes needed to add their own bits of flare to it (of course). So it ended up being so much more than a blank case.

They were so surprised to see the rover virtually speed off across the deck without any batteries or additional inputs.  Even though we made this on a sorta cloudy day, it still worked very very well.  Plus, the clouds helped the kiddoes see that it genuinely was the sun which was powering their vehicle, since it would slow down and speed up based on the amount of incoming sunshine.  By the end, they figured out to adjust the panels to pick up the most solar energy.

--Little Miss Crazy

Speed, acceleration, and velocity

We discussed our terms for the week-- speed, acceleration, and velocity-- but more than anything else, we just had a lot of fun using our speed.  We raced cars down ramps.  We measured distances with our measuring tape.  We used a stopwatch to time ourselves running up and down the hallway, the backyard, the road, etc.  We were introduced to another great song from Mr. Edmonds. We ran and ran and ran. 

If there's one thing boys enjoy, it's running.  They will do it every chance they get.  Throw in a couple fun tools, like a measuring tape and a stopwatch, and they'll do it even more.  And sometimes, it's just that simple.

--Little Miss Crazy

Mass, weight, and density

If I could go back in time, I probably would skip this week of science. I wanted to give the kiddoes some concept of what mass is before discussing Newton's second law.  Honestly, I probably could have just let them think it's the same as weight and moved on.  I don't think they really got much understanding out of our discussion or demonstrations.

However, there was one big bonus to my search for content for this unanticipated week of learning; this was the week I was introduced to Mr. Edmonds' science songs on youtube.  Believe me, I had a hard time finding resources on the differences between mass & weight suitable for my kiddoes' age range. "Mass vs weight" quickly became a favorite song around the house.  During our additional discussions, we did also listen to "Density," but it did not take off nearly as well in my house (I loved it, being a Wicked fan, but for the kids it was not easy to recognize or catchy enough.)

We started off trying to get an idea of the difference between mass and weight, which of course led to a conversation about weight on other planets compared to Earth.  The kids got real kick out of that discussion.

The week would have been awfully short if we had left things there, so I threw in some fun activities related to density.  We observed different liquids creating layers in a glass.  We tried different items to see what would float or sink.  We measured how much water was displaced when a heavy but small item sinks compared to a light but large item (bringing the discussion back around to the difference between weight and mass).

And of course, I got no pictures of science this week, so I'll leave you with a couple pics from our continued time playing with water: air takes up space!

The boys had a little trouble keeping the cup straight so the air didn't escape, but they had a lot of fun trying.

This was not part of our lesson or a planned activity, but there's always time for a little extra learning fun, especially when the kiddoes request it!

--Little Miss Crazy

Energy through electronics

Mr. Crazy is an electrician.  His abilities, interests, and occupations have ranged pretty far from the norm in that particular field, but at his base, he's an electrician.  When I asked him to "substitute teach" during our energy unit, he was pretty excited.  We both knew going in that he wouldn't stick with my plans and framework, so I asked him to be sure he discussed potential and kinetic energy (the base topics for the week) and then let him do things his own way.  He knew exactly what he wanted to do, and he found some pretty neat stuff to use for his demonstrations.

On random shopping trips, we picked up both a Radio Shack snap kit and Snap Circuits Light.  These are some awesome little kits.  I heartily recommend them to anyone with a kiddo interested in electronics (or a parent who wants their kiddo to see how things work).  This is a perfectly safe way to explore electricity, even with kiddoes at a relatively young age.  All the components snap together (hence the name) making simple and complex circuits easy to explain and understand.

Mr. Crazy started his circuits (aka racetracks) very, very simple and explained each part as he put it together. ("The light can't turn on because it isn't connected to the battery yet; we have to add a line to connect them.")  By the end of the lesson, his racetracks had gotten quite complex.  The kiddoes took guesses about what would happen when circuits were connected different ways (with switches, alternate paths, etc).  They identified where the energy/ electricity was in motion and where it was "waiting."  They had SO much fun with the crazy flying saucer and lights.

Mr. Crazy turned the flying saucer into a fan and everyone wanted to feel the air.

The kiddoes learned a lot about electric circuits, learned a little about energy, and got to have a lot of fun with their substitute teacher. (As an added bonus, Hulk was able to retain this information really well; he was very excited about it and really enjoyed learning electronics.  Now Mr. Crazy has some more one on one electronics fun planned for the two of them.)

Our continued discussion of potential and kinetic energy led to another very fun afternoon.  I used a simple rubber band to show potential (pulled back and held still-- holding all the energy from being stretched) and kinetic (let 'er rip and they really fly).  For more rubber band fun, check out E is for Explore!; I love combining topics!  Going a little farther with this idea, we made slingshots from rubber bands and toilet paper tubes (instructions at PBSKids Design Squad).  We used ping pong balls for the projectiles and brought out little green army men to test them out.  Crazy projectile fun ensued:

I had planned on doing some additional demonstrations, but the kiddoes spent most of the rest of the day setting up and knocking over little green army men, so they'll be left for another time.  We never complain when science activities get extended. :)

--Little Miss Crazy

Work and energy introduction

Kids have heard the word energy tons of times in their lives.  Mine usually hear something like, "Go run around outside and use up some of your energy!"

To kick off our energy unit, Athena read Energy Makes Things Happen which introduced the scientific idea of energy. It wasn't very hard for my kiddoes to take their basic understanding and apply it to energy in science.  We discussed different forms of energy that they are already familiar with-- light, sound, heat, etc.  We also briefly discussed fuels and where we get our energy.

Something has energy when it is capable of doing work, although the scientific definition of WORK was harder for the kiddoes to understand. We discussed work at the beginning of our simple machines unit, but it was very brief, so we learned it all over again now with energy.  When a force moves an object over a distance, work is done.

 

We reviewed distance by measuring the width of apples, height of ourselves, length of the room, etc. (and everyone loves a good excuse to play with the measuring tape). We reviewed force quickly, too, although they have a pretty good understanding of force. Then we moved on to a few easy examples of work: if I hold a feather up high, then drop it, that is work because the force of gravity moves the feather the distance down to the ground.   If I push an apple across the table, my force is a push and the distance is across the table, so I am doing work.

They really had fun when we tried some examples where NO work was done.  I asked them to push the kitchen wall as hard as they could.  Since the wall doesn't move, no work was done-- but they sure were tired for having done no work. lol

The kids always enjoy it when I can find a song related to what we're going over.  SchoolHouse Rock! has some good ones, although not much related to science.  However, we have found a treasure for physics-related songs; a science teacher made parodies of well-known oldies, rewriting them with ideas from science.  Most of them explain not only the terms, but their units and some formulas.  We are only doing a basic overview of the ideas of physics and leaving the math for our next run-through, but the kids still end up memorizing the songs and singing them all the time.  This week's song, "The Work and Power Song," was no exception.  These songs are great because my kiddoes already know the tune and because the lyrics include a lot of repetition that they can catch and easily remember.

I get excited when the kiddoes can take a concept they already know (such as energy) and bridge the gaps to understand how science defines that concept.

--Little Miss Crazy

Bouncing, Balloons, and Balance

Gravity is easy-peasy to study.  We dropped things.  And jumped off things.  And bounced balls.  And watched my new favorite SchoolHouse Rock! song & video about gravity.  (Goblin LOVES this song and made us listen to it over and over for days!)  We also briefly discussed 2 physicists who are part of the history of our understanding of gravity, Galileo and Isaac Newton.  The kids colored a picture of Isaac Newton from Color Me Physics  (I'm saving the Galileo page for when we get into astronomy).

Although the kids had a BLAST jumping around the house and dropping everything they could find, the real fun came when we investigated an object's center of gravity.  We took a balloon and filled it with water (you can use a water balloon if you prefer, I found it worked just fine with a regular balloon I had on hand), then tied it off.  We put that balloon INSIDE of another balloon, which I blew up like normal.  (The tricky part was getting the water-filled balloon into the empty balloon, so I enlisted help from Athena.)

Here's what it looks like when you're ready to play (with the light behind it, you can see the smaller water-filled balloon inside your standard balloon:

The balloon filled with water moves around inside the balloon filled with air, changing its center of gravity-- and making for some fun crazy games!  (FYI, our first balloon popped-- not the water one, just the outer one--after the kids took it outside, so we quickly made another.)  For our basic demonstration, I just had the kids toss it back and forth between them, noticing how hard it was to make the balloon move in the direction they wanted.  (We also blew up a balloon-- without putting a false center of gravity inside-- to use as a comparison.)  Afterward, the kids came up with their own ideas of how to play with the balloon, which was awesome to see.

Finally we discussed how an object's center of gravity affects its balance.  We tried to balance quarters on top of pencils, then added forks on either side to create a larger center, making it easier to balance.

Our physics kit also included this goofy clown balancing on his nose.  We attached a few paperclips to the hands and balanced him on a pencil too.  Goblin really liked this guy, so he decided to try to balance it on his nose-- mission accomplished!

Every good science lesson needs to be recorded in journals.

I love seeing their pictures and hearing their explanations.  When they understand what they've learned, it is very simple and to the point, and you can always tell what makes an impact.

--Little Miss Crazy

Magic and Hovercrafts

You know it's going to be a good week when your science lessons feel like magic tricks . . . and they work!  I've always been terrible at magic tricks: even when I know how they work and how to do them, they never seem to work for me.  It can be a bit depressing.  So I was a little worried about whether or not I would be able to pull off our lessons this week.  But it the end: Voila!

When you remove the card (quickly-- flicking it forward works much better than pulling it out, for your information), the pennies stay in place . . . until gravity pulls them down into the cup. One basic, concrete example of the concept of inertia: an object at rest tends to stay at rest (until acted on by a force).

It's such a simple idea, but they kept doing this one (and asking me to do it) over and over again, long after lesson time was done.

We also made a stack of pennies and pushed a single penny across the table into it, replacing the bottom coin.  This one did not work every time, but it worked at least half of the times we tried it, which is pretty good in my book.

Being a bit of a worrier, I drew the line at trying to pull a tablecloth out from under a table full of dishes.  If I could have gotten it down, it would have been pretty impressive.  Maybe next time we talk about Newton's laws. :)

Many of my favorite ideas for our studies (some that we used and some that we didn't) came from E is for Explore!. I strongly suggest checking out what they have compiled.

Continuing on to the flip side of Newton's First Law-- objects in motion tend to remain in motion-- I added in a discussion of friction, which gave us the opportunity to play with an air puck aka a hovercraft!  We made ours from the materials that came in our Physics kit, but there is a great how-to on Scribbit to make one using common household materials.

To start out, I hid the balloon and tapped the puck, moving it across the table to show the children how far it would go.  Then we built the hovercraft and let it float across the tabletop to see how much farther it would go with a cushion of air underneath.  I asked the kids why the distances the puck travelled were so different.  It took some thinking, but they figured out that the puck rubbed on the table and that slowed it down.  Then, we all rubbed our hands together quickly to see how the heat builds up and lets us know there is friction between them.

For a little fun at the end of the day, we also watched The Magic School Bus Plays Ball on youtube, which has a great discussion of friction and force as well.

I was so tempted to run right out and buy a kids' air hockey table to go along with our discussion, but that did seem a little overboard.  The kiddoes used our air puck on the kitchen table in the same way, but bumpers would have been a great addition!  They batted it back and forth from one end of the table to the other until all the air was gone, then blew it back up and started again!

Most of what we did this week was so simple, which proved to be a big part of what made it all work so well.  The kids were fascinated to see everyday items used in ways that seem magical and amazing.  And not only could they watch the magic, but they could actually DO the magic themselves. Based on the entries in their journals afterwards, they even understood WHY the magic was working.  Watching learning happen right before my eyes is my favorite kind of magic. ;)

--Little Miss Crazy

Uplifting Screws

I must admit, I think I had way more fun than the kids working on our screw unit.  When I find something genuinely clever to add into our mix of information, demonstration, and minor experimentation, I get very excited about it.  The water wheel was one of those clever additions and so was this weeks extra bit of fun: the Archimedes screw!  But before I get too far ahead of myself, back to the lesson overall.

When I explained to the kids that our simple machine for this week was the screw, they looked at me like I was crazy.  They KNOW screws.  The other machines might have been simple and easy to recognize, but at least they did more than one thing.  Well, by the end of the day, the kiddoes did realize that screws are used both to hold things together and lift things, but I'm pretty sure they still thought I was crazy to be so giddy-excited over something as boring as screws.

The one thing they did get excited about was lunch.  I rarely incorporate meals into our lessons, but since we were already wrapping paper triangles around pencils to demonstrate the relationship between the inclined plane and the screw, it was easy to add on wrapping triangle croissants around hot dogs to make edible screws!  Sometimes it's pretty easy to get them excited about science, too.

We also made little paper helicopters that twirl down to the ground like screws, so they don't just crash down to the ground.  Anything that can be made from paper always seems to be a hit and has the added bonus of being simple and fast.  I used the template provided in Starting with Science: Simple Machines, but it would be easy to make one without a guide.  As long as the paper has a middle section to point down and 2 propellers to catch the air and cause it to turn, it should work.

We took a plastic cylinder (you could also use a Pringles can) and wrapped some plastic tubing (meant for an aquarium) around it, then used this to transport water up to a higher container.

Finally, the Archimedes screw.  I found a tutorial here to make one from a plastic bottle, paperboard/ cardstock, and a dowel/ pencil.  The process is really simple.  Ours got a little stuck after a while, but it still accomplished its purpose.  Next time I would use a stronger material for the spiral and make sure that the bottle is the same width all the way through so there are no gaps at the sides. (By the way, I realized I had no pictures of this one, so I went back and took a few quick ones, and I was using it upside down!  Oops!  lol)

All in all, a very fun and successful unit. The kids definitely got the idea and had some fun (even if I had a bit more!)  We'll be doing some quick review, then it's on to energy!

--Little Miss Crazy

Cutting with Wedges

We got started on science a little late this week, but all of our little projects were a lot of fun, so it was still a good lesson.  We talked about the simple machine called the wedge.  I started out using the same ramp we played with during our discussion of inclined planes last week so that they could have a visual reminder and be able to actually see how the two are related.

Athena read the page on wedges aloud from our mini-book on simple machines, and everyone came up with a few examples of wedges from around the house.  They had a hard time identifying these at the beginning of our discussion, so I pulled our the Usborne Science Encyclopedia to give them a little more information and provide more examples.

Our first demonstration came from Starting with Science: Simple Machines.  I cut some carrot slices and asked the kids to try to push them into an apple with no extra tools.  They made a couple good dents, but weren't able to pierce the skin.

Then I cut the carrot slices into little wedge shapes, and they tried again.

Success!  It took much less effort to push the carrot pieces into the apple when they were shaped like wedges.  And we were able to make some fun goofy faces, too. :)

Then it was time to take a little art break and color papers.  The kids came up with some nice drawings, and it was almost a shame to turn them into paper airplanes at the end.  I used this time to explain how wedges can "cut" through more abstract things, like air and water, as well as literally cutting like a knife.

Our final (and most fun) project was definitely the boats.   The kids were a bit more fascinated with the rubber band motors than the wedge shape that allowed the boats to push through the water with ease, but it was still a good demonstration.  We did try pushing the boats facing forward (wedge in front) and backward (flat front) to compare the effort needed to get them through, but it was tough for the kiddoes to tell the difference.

By the end of the lesson, they were able to find several new examples of wedges around the house and explain for their journals how they do work.  We were able to push through some unclear examples and enjoy a little goofing around and still get the point across.  Next week is our last simple machine before we get to put them all together for some goofy compound machine building for review, so I'm getting pretty excited checking out all the fun we have in store.

--Little Miss Crazy

What is a force?

Our first week of science was simple and fun. I introduced the idea of force as a push or pull to the children, gave them a bunch of examples, asked them to think of some of their own examples.  We watched an episode of Sid the Science Kid about forces (Sid's Super Kick). We built a simple Newton-meter (from the ScienceWiz Physics kit) to measure forces during the rest of the unit and used it to measure gravity pulling on an apple.

Then they all got out their science journals and drew a picture related to what we'd discussed with a written explanation.  Well, Athena wrote her explanation; Hulk and Goblin explained theirs to me, and I did the writing.

Then we went outside to play in the backyard, and that was where the real learning fun began.   While they were playing, I asked them which kind of forces they were using (and which were acting ON them) and the directions of the forces.

They were really excited that they understood what I was asking and soon, all three were shouting out answers and coming up with lots of their own ideas about forces and how they work.

This was probably their favorite demonstration of the day, and they kept at it for a long time.  They each tried hitting the ball first very softly, then a "normal" hit, and finally as hard as they could to see what would happen each time.  They discovered that the harder you hit the ball, the farther and faster it goes.  Little scientists coming up with their own ideas and testing them; it's all natural for them.

--Little Miss Crazy