Boxi Math

K–12 · English & 中文

Maths you can see, from counting to calculus.

Short videos that show why maths works — one idea each, drawn so you can see it. Free, in English and Chinese.

Watch by stage, not by age. Move on when it makes sense, not when the calendar says so.

Stages

0

Early Start

How many?

about 3–6 · 0 videos

1

The World of Numbers

Why is this way of computing right?

about 6–9 · 5 videos

2

New Numbers

When the unit changes, what happens to the number?

about 9–12 · 10 videos

3

Structure

Can we say it in general?

about 12–15 · 12 videos

4

Change and Relations

How does it change? Why must it be so?

about 15–18 · 12 videos

Six seeds

Before any topic, six ideas worth planting early. Every video says which seeds it grows.

S-1

Numbers are amounts

See three without counting; five can be two and three; 7 sits a little to the left of 10 on the number line.

 S-2

The equals sign is a balance

In 3 + 4 = □ + 5 the box is 2, not 7. “=” means both sides are the same amount, not “here comes the answer”.

 S-3

Units can be redefined

Ten ones make one ten; cut a bar into three and one piece is a new unit; 1/2 and 2/4 are the same point.

 S-4

Shapes can move

Cut, slide, turn or flip a shape and its area stays the same; two equal triangles make a parallelogram.

 S-5

Patterns can be put into words

What comes after 2, 4, 6? Say the rule in your own words — then ask: must it be so?

 S-6

Mistakes are fine — try it

Guess, check, fix. “I don't know yet, but I can try n = 1.”