Pixel Puzzle #257

Pixel Puzzle 257 card

Challenge type: Pixel Puzzles  ·  Difficulty: ★★★★☆ Tricky  ·  Grid: 12 × 12 · Colours: 4

Computers store pictures as lists of numbers, one number for each pixel. You’re about to be the computer!

Pixel puzzle 257: a 12 by 12 number grid with a colour key.
Colour each square to match its number.

The colour key

  • 1 = green
  • 2 = white
  • 3 = orange
  • 4 = navy
  • 0 (shown as ·) = leave it white

The number grid

Here’s the same grid as a table. You can copy it onto squared paper, one number per square.

Row123456789101112
1············
2············
3··11111111··
4·1111··1111·
5·1112··2111·
6·1134··4311·
7··31111113··
8··11333311··
9··11111111··
10··11111111··
11···1····1···
12············
Need a hint?

The picture is a pixel creature! Start with the colour that appears most, then fill in the details.

Grown-ups: Print the grid picture or copy it onto squared paper. This is exactly how images are stored: a grid of numbers, where each number means a colour. It’s a lovely calm activity for younger children too.

For teachers and grown-ups

Skills practised: Data representation, following a key, and attention to detail.

The big idea: A digital picture is a grid of numbers. Each number stands for a colour.

Questions to ask:

  • How many pixels are in this picture?
  • Which colour appears most often?
  • How could you describe the picture in fewer numbers? (Hint: count runs of the same colour.)

Take it further: Children design their own pixel picture on squared paper and write it out as numbers for a partner.