Tech ed for your homeschool, ages 7 to 18

Your child watches two balls bounce around a ring of eight pegs that play notes, then switches the scale from Major to Minor while it plays. The balls bounce exactly the same way, but the mood of the music changes. They find out which notes changed, compare five scales, and set up a ring to fit a mood of their own for you to guess.

Your child watches a fish, a snake and a lizard swim in tight circles and finds out why the fish is the only one that cannot close its ring. Under the skin each body is a chain of joints, and each joint can bend only so far, so the bends add up like angles. By the end your child has changed the fish until it curls all the way around.

Your child plays a short platform game, changes one number, the jump power, and finds the player stuck in a valley it climbed out of a minute ago. They learn that gravity, jump and speed are variables the game reads, find the same numbers in the game's code, and tune the game to feel the way they want. At the end you play it and guess what they changed.

A summer camp sends back the ball cap it ordered, because the counselors' necks and ears burn by lunch. Your child reads the camp's brief, four requirements with numbers in them, and designs a 3D sun hat that meets every one. They find out that a design is done when the numbers say so, not when it looks finished.

Your child opens a combat robot whose spinning blade empties its battery in under 7 seconds and then cuts out mid-fight. They read three numbers the app shows and work out the run time themselves: the battery divided by what is lost each second. Then they find the lightest battery cells that keep the blade spinning for at least 15 seconds, because every kilogram spent on cells is weight the robot cannot use for anything else.

Your child builds a computer from real parts on a 3D workbench, from the CPU and its cooler to the cables, and turns it on. Then they take one part out at a time, guess what the computer will say, and turn it on to find out. By the end they can tell what each part does from what goes wrong without it.

Your child opens a 3D jack-o'-lantern whose face is carved three different ways, predicts which parts will glow in the dark, and turns the lights off to find out. It is a real light experiment: what passes through, what glows, what stays dark, and why the face on the wall is bigger than the face on the pumpkin.

Your child makes a thunderstorm in a weather simulator, then takes it apart one ingredient at a time to find out what a storm needs: moisture, rising air that stays warm, and something to push the air up. Then they fix days that make no storm, saying what will happen before each test.