Halving fun!

Summary

Students practise halving numbers within 20 in a race to reach 30.

Curriculum content

• Find half of an amount within 20

Materials

Card sets

• 1 set of Mathletics number cards 2 to 20 (only even numbers) 2-20

Concrete

• 2 different coloured counters

Printables

• Number line from 0 to 30 Download number line 0-30 - CAL Download number line 0-30 - Tabloid-CA

How to play

Set up

1. Arrange students into pairs.
2. Remove all odd numbers from the Mathletics number card set.
3. Shuffle or mix up the cards and place them in a pile face down.
4. Each student places their counter on 0 on the number line

Rules

1. Player 1 turns over a card.
2. Player 1 halves the number shown on the card and moves their counter that many spaces.
3. Player 2 turns over a card.
4. Player 2 halves the number shown on the card and moves their counter that many spaces.
5. Play continues until each player has had 5 turns.
6. If a player would go beyond 30 if their number was added, they need to subtract instead.
7. The winner is the player closest to 30 after 5 turns.

Variations

CHANGE it down

• Use Mathletics number cards 1 to 10 (even numbers only) and race to 20.
• Provide extra counters or objects for calculating halves.

CHANGE it up

• The winner is the first person to land on 30 exactly.

What to look for

• Are students able to fluently halve numbers within 20?
• Do students rely on concrete resources?