I've been thinking more about simple science experiments that require little more than imagination and creativity. Maybe we can each post ideas to this thread and come up with the Homeschool Spot's Guide to Science Experiments! For starters, I mentioned in the 'Relaxed Science' thread a simple experiment to calculate the speed of sound using echos. Once the speed is known, a child should be able to tell how far away is a lightning bolt based on the time difference between lightning flash and thunder roll. Another important principle in science is probability. What about putting a stick in the ground and throwing stones at it from 30 yards? Measure how far each stone is from the stick and plot a graph. There are many simple variations on this: Aiming darts at the center of a dartboard, shooting arrows at a target, measuring how long shoppers take to walk an aisle, and so on. Very soon, the whole principle of probability becomes second nature. Believe it or not, I once read of a PhD thesis based on painting numbers on the shells of snails and tracking their movements each day around a field. This is essentially the same as tracking birds and whales and the like except that snails are a little easier to track! Not all of us live in locales where snails are found, but you can learn some interesting and unexpected things when tracking creatures of any type. Energy efficiency experiments around the home. Start turning off lights when they don't need to be on and determine from utility bills how much is saved. Reduce the amount of water used to flush toilets and determine how much water is saved every month. Add drapes to a large window and close them at night to determine whether this affects the heating bill. OK - any creative ideas?
If you happen to have an electronic keyboard available to you, you can cut sections of plastic pipe, place them over the speaker, and observe which notes are amplified by resonance for which lengths. Estimate the sound volume on a simple scale. Plot volume against note frequency (which you can readily look up). Estimate the maximum volume's frequency for each length. Find relationship between length and frequency. If you have enough mathematics, use the result to calculate the speed of sound. This simple experiment allows you to learn about many aspects of sound. If an electronic keyboard is unavailable, you can get tuning forks or find software that turns your computer into an electronic keyboard. You'll probably have to have a speaker attached to your computer, but many already have this.
There's a famous pedestrian bridge that crosses the river flowing through Prague. I remember walking the bridge one cold evening and watching someone play an instrument he'd made out of water glasses. He'd circle his finger around the rim of the glass to play a note and had arranged glasses in the form of multiple 'keyboards' so he could play as many as four notes at one time. To tune the 'notes', he had a bottle from which he could add more water to a glass. If you have some cheap glasses available and your child can get a note from one by rubbing their finger around the rim, maybe have them create their own instrument and learn to play some tunes. It would be a great party trick for visiting friends and family. PS - I found a YouTue video of this guy. It's fascinating to watch.
You can readily make your own glass harmonica. Google the following: glass harmonica young engineers. Sorry for the indirect reference. I'm not allowed to post links. Note that you can do lots of neat science with this arrangement as well as play music. Heavy-walled (usuallly cheap) glasses, those with non-uniform walls (also cheap), and glasses without stems don't work as well as decent wine glasses. Quartz works best of all, but is prohibitively expensive. If you've never heard the sound before, you're in for a treat, albeit disturbing to some people due to the purity of sound and its odd non-directionality.
OK - here he's playing something a little more difficult - from 'The Moldau' by Smetana. Maybe this is more appropriate for a music lesson than for a science lesson. To make it more a science experiment, here he's tuning his glasses.
If you do this at home, ask your student to predict what will happen to the sound as the glass fills with water.
If you're looking for some synthetic chemistry to do at home, you'll not find many ideas that are safe. For an inorganic synthesis, try making Rochelle salt, a double salt, from cream of tartar and washing soda. When you have the salt made, test it by dehydrating it in your oven. You weigh it before and after dehydration to see that the ratio is correct for the expected formula. I have some pictures but once again cannot post the link. You also can do the standard Analysis of Hydrates experiment at home. You only have to have a postal scale, although better scales might be more "scientific." Put some Epsom salt on aluminum foil (weighing the foil and then the foil+salt). Heat at 450ºF for an hour. Weigh again. Repeat for different masses. Calculate the number of water molecules in each formula mass of Epsom salt. How does this number change with mass? Do an error analysis? How can you improve precision? This experiment really works.
There's a book called 730 Easy Science Experiments with Everyday Materials that I like. Most of the supplies and materials are things you'll find around the house. It's on the clearance rack at my Border's store these days for $10. Another great resource using simple materials is How the Weather Works 100 Ways Parents and Kids Can Share the Secrets of the Atmosphere by Michael Allaby. I can't post links yet but there are cheaper copies on amazon than the one that pops up first when you do a search. You also might check the library.
I am ill. I wrote a nice long post and then hit 'post' and then left the page as I saw the 'your cookies have expired' or something message so the whole thing was lost. Fine. I am summarizing, sorry. I listed a couple random ones, but I think my best idea comes from the Mythbusters. About 75% of the experiments they do should NOT be replicated from home, but there are several that can. I actually browsed the show list and posted a ton, but here is the simplified version to encourage you to go check out the show (which incidentally is pretty kid-friendly), or if you're already watching to look for kid-proof experiments: adding mentos to diet coke (which reminded me of the old 'build a volcano' vinegar-and-baking soda experiment), racing a matchbox car on an extremely long track, checking the bacteria in your house to find the dirtiest place, building a boat or car to see if it floats/rolls & what makes the best material, does a banana peel make you slip, can ninjas walk on water (for older kids), can you teach an old dog new tricks, does an eye patch on a pirate improve night vision, comparing milage between the windows down and the a/c or a tailgate up or down, interweaving two phone book pages (the show used two tanks to pull them apart, but just tug-of-war would be awesomely fun), germs and double dipping. Oh you know what else I said? I just remembered. I think it is REALLY important to let your kids devise experiments, even if they fail. Or you give them a question and have them come up with an experiment. "What kind of an experiment can you come up with to demonstrate what effect friction has on motion?" Remind them that "real" scientists do a lot of research before starting. That research can help them come up with the experiment themselves. But allowing them, even little ones, to come up with the experiment encourages scientific thinking. Sorry if that comes out as abrupt, I'm tetchy after I type something and lose it, and I can never remember if I am repeating myself in the second post, LOL.
