Four Go

Four Go

Four Go printable sheet

Draw a number line on a piece of paper, marked from $0$ to $20$, like this:

(You could print off this sheet of number lines.)

This challenge is a game for two players. The first player chooses two numbers in this grid and either multiplies or divides them.
 

They then mark the answer to the calculation on the number line. The second player then chooses two numbers and either $\times$ or $\div$, and marks that number in a different colour on the number line.

If the answer is too big or too small to be marked on the number line, the player misses a go.

The winner is the player to get four marks in a row with none of their opponent's marks in between.

What good ways do you have of winning the game?

Does it matter if you go first or second?

[This game is adapted from a SMILE Centre card.]

Why do this problem?

This game gives children the opportunity to estimate answers to calculations in a motivating context, and gives plenty of practice in multiplication and division. Playing strategically involves higher-order thinking and the need to think ahead. 

Possible approach

You could play the game on the board against another adult (or a child who has been told the rules), but without saying anything about the rules to the whole group. You could write down each calculation as you go along. Invite the class to watch the game in action and after a few moves, ask them to suggest what they think the rules might be. How might the game be won? Having discussed the possibilities as a whole class, explain the rules as described in the problem itself and set the children off playing in pairs on some number lines.

Key questions

Possible extension

Possible support