Explode a number

Summary

Students work together to write as many equations as possible for a given number before the timer runs out.

Curriculum content

• Add and subtract
• Multiply and divide
• Double and halve
• Use known number facts

Materials

Card sets

• 1 set of Mathletics number cards 0 to 9 1-9

Concrete

• Paper and pencils or markers

How to play

Set up

1. Arrange students into small groups or play as a class.
2. Give each group a piece of paper and coloured pencils or markers.

Rules

1. Select 2 number cards and arrange them to make a 2-digit number.
2. Set a timer for 2 minutes.
3. Ask players to write as many equations as possible that have that number as the answer before the timer runs out.
4. Groups or class score 1 point for every correct calculation and 5 points for each different operation used.

Variations

CHANGE it down

• Use only cards 0 to 5.
• Remove the timer and ask students to work on differentiated target numbers as an assessment.
• Work as a whole class inviting each pair of partners to share an idea.

CHANGE it up

• Ask students to work individually towards a target number.
• Give students types of calculation to focus on.
• Ask students to create their own rules for the game.

What to look for

• Are students relying on one operation?
• Are students using known facts to calculate? For example once they have found one number sentence are they using this to give more answers?
• Are students using mathematical language correctly?
• Are students able to accurately record number sentences?