Topics

One idea at a time: what it is, where kids get stuck, how to show it at home, and the games that teach it.

• Why do we have seasons?

  Not because Earth gets closer to the Sun. The tilt of Earth's axis does it, and a 10-year-old can see how with a lamp and a ball.

• Simple circuits for kids: battery, switch and bulb

  Electricity only flows round a closed loop. Once a child sees the loop, switches, broken wires and dead bulbs all make sense.

• Adding numbers up to 10: what helps a 5-year-old

  Adding is putting two groups together and counting the whole. Children move through three stages, and knowing which one yours is at makes practice easy.

• How the internet delivers a message, explained for a 10-year-old

  There is no wire from you to your friend. Your message is cut into numbered packets that each find their own way and get put back together at the end.

• Why the Moon changes shape

  The Moon doesn't change. Half of it is always lit by the Sun; we just see that lit half from different angles as it goes round us.

• Counting US coins: penny, nickel, dime, quarter

  The dime is the smallest coin and worth more than the penny or the nickel. Value is not size, and that is the first thing to teach.