Physics for Kids

2nd Newton Law — Forces, Motion & Gravity

Gravity Lesson (PDF) — 12-slide deck covering F = m·a, gravity, and Newton’s Law of Universal Gravitation

Falling Ball — watch a ball fall under gravity and see F = m·a in action
Gravity Playground — create and launch objects in a free-form gravity sandbox
Ground Gravity Lab — drop a ball on the Moon, Mars, Earth or Jupiter; change its mass and see that it still falls at the same rate
Two Planets Pulling — watch two planets attract each other with F = G·m₁·m₂ / r²

Electricity Lesson (PDF) — 15-slide deck on electric current, conductors and insulators, the direction of current, and series and parallel circuits
Materials Lesson: Conductors & Insulators (PDF) — 15-slide deck on testing a material, metals, surprising conductors (graphite, salt water, the human body), the insulator families, semiconductors, and the right material in the right place

Circuit Maze — build a path for the current from A (+) to B (−) with pieces that may be conductors or insulators; watch out for diodes and short circuits
Lamp Detective — series or parallel? Predict which lamps shine brightest, which go out when one is unscrewed, and what each switch controls, then test it
Materials Lab — four activities: test objects with a lamp or an LED, sort conductors and insulators against the clock, pick the right materials in the Electrician’s Workshop, and take the quiz

A circuit you can ride — how Étienne, the French electric engine, uses a complete loop, conductors and insulators to race along the rails

Magnets Lesson (PDF) — 15-slide deck on poles, attraction and repulsion, magnetic fields, domains, permanent and temporary magnets, and electromagnets

Magnet Lab — six activities: explore poles and fields, line up the domains in a nail, guess what a magnet attracts, build an electromagnet, steer a steel ball through a maze, and take the quiz

Gears Lesson (PDF) — 15-slide deck on toothed wheels, direction of rotation, speed and force, bike gears, chains and belts, bevel gears, worm gears, and rack and pinion

Gear Lab — five activities: build gear trains, solve eight gear puzzles, turn a chain, a belt, an egg beater, a worm gear and a cog railway, shift gears on a bike ride over hills, and take the quiz

core.js — gear geometry: when two gears mesh, and how speed and direction pass from one gear to the next
puzzles.js — the gear puzzles: pegs, a motor and machines to drive
machines.js — the chain, the belt, the egg beater, the worm gear and the cog railway
bike.js — the bike: the force pushing on the road in each gear