Elementary science lesson

I love my Newton's cradle, and various versions have amused me for decades now. Harrod's popularized them as desktop toys way back when, but not because they're scientifical.

They're just plain fun.

They're also as obvious as the nose on a polar bear's face. Five balls banging against each other, in unexpected yet predictable and repeatable ways.

Just don't use the words inertia or force, or, Zeus forbid, Newton's Third Law.

Give a pair of children a Newton's cradle. Hold up a ball (or let one of them do it), and let it fall.
Hold up two, and do the same.

Have the children take turns predicting what will happen.

Then put the toys away for a few days.

No worksheets. No quizzes. No fancy words. Just a piece of the universe delivered unadulterated to the few minds left on Earth capable of seeing things for what they simply are.

Newton's cradle by DemonDeluxe via Wikiedia, unde CC

Cheap tools for kindergarten (Part 4)

Newton's cradle is a toy.

Isaac Newton did not invent it, nor did he invent the Laws of Motion. They just are. He uncovered what always, as far as we know, existed.

If you use this in class, do not show the kids the various permutations--they will find them if you let them be. Do not tell them it models the Law of Conservation of Momentum.

And if they ask for an explanation, tell them that everything moving (which is everything) has a certain amount of oomph, depending on how much stuff it has, and which direction it's moving. If they ask for more, tell them that we have just so much oomph in the world, no less, no more, and that it can be passed along between things.

If they ask why, tell them no one knows why. If you tell them otherwise, you will confuse them. Mutatio motus just is.

Just let them play, touching and seeing and hearing the world as it is.

You can play with a computerized version here, using different numbers of balls. 

But why not just use the real thing?
Yes, I know Newton was reporting what others had already shown.... 

The cradle pictured is by Dominique Toussaint from Wikimedia.