What is a mystery picture?

A grid of squares, each with a number or a math problem. Children colour every square with the colour the key gives for its number, and a picture appears. The picture’s name is only printed on the answer key, so it stays a surprise.

Can the squares show math facts?

Yes. Choose Sums for addition within 10, like 3+4, or Take away for subtraction within 20, like 12–5. Children work out the answer to find the colour, so a page is 144 to 400 facts of practice.

Which pictures are there?

Fruit, animals, a bus, a house, a rainbow and seasonal pictures such as a pumpkin, a turkey and a Christmas tree. Each one is drawn from a full-colour illustration, so the finished picture looks right.

How many colours do children need?

At most seven, and only everyday crayon colours: red, orange, yellow, green, blue, purple, brown, pink, grey and black. Squares in the background say “leave white”.

Which grid size should I choose?

12 by 12 for pre-K and Kindergarten, 16 by 16 for most children, and 20 by 20 for older children who like a longer project.

Colour by Number Mystery Pictures: Numbers, Addition and Subtraction

Why children love them

A mystery picture turns a page of number recognition or math facts into a puzzle with a payoff. Children want to see what the picture is, so they keep going, and every square they colour is one more fact practised. Because a wrong answer shows up as a square of the wrong colour, they can often spot and fix their own mistakes.

Three ways to play

Numbers. Match each number to its colour in the key.
Sums. Addition within 10, every answer from 2 to 10.
Take away. Subtraction within 20, every answer from 2 to 10.

More puzzles

Try dot to dot for counting in order and mazes for pencil control. For more practice with the same facts, the addition worksheets come with answer keys too.

Provincial curriculum links

BC KNumber concepts to 10, including linking sets to numerals.
BC Grade 1Addition and subtraction to 20, with mental strategies such as making 10 and doubles.
BC Grade 2Fluency with addition and subtraction facts to 20.
ON Grade 1–2The Number strand builds addition and subtraction with numbers up to 50, then up to 200.

Colour by number isn’t a curriculum topic; its value is the practice inside it. The Numbers mode is numeral recognition for Kindergarten, the Sums mode (within 10) fits Grade 1, and the Take away mode (within 20) matches the facts BC students work on in Grade 2. BC expects most students to recall addition facts to 20 by the end of Grade 3, so a mystery picture is a welcome change from a page of drills.

The pumpkin and turkey pictures suit Canadian Thanksgiving, which falls on the second Monday of October.

Summarized in our own words from the BC Mathematics curriculum (K–3) and Ontario’s overview of The Ontario Curriculum, Grades 1–8: Mathematics (2020).