# Biscuit Boxes

Achievement Objectives
NA2-1: Use simple additive strategies with whole numbers and fractions.
NA2-1: Use simple additive strategies with whole numbers and fractions.
Specific Learning Outcomes

Solve division problems by sharing.

Description of Mathematics

Number Framework Stage 5

Required Resource Materials
Unifix cubes

Small cardboard packets (optional)

Activity

#### Using Materials

Problem: I’m giving you all a job at the biscuit factory. I want you to pretend that these cubes are biscuits. Make twenty biscuits for me. Encourage the students to make their biscuits in stacks with five breaks of colour for easy counting:

Now you have to put the biscuits into packets. You are going to put four biscuits in each packet. How many packets will you be able to make with twenty biscuits?

Encourage the students to predict the number of packets. Some may do this using the colour pattern of the stacks, take one cube off each group of five to form four fours and enough singles to form another four.

Allow the students to divide the cubes up into fours and record the operation, 20 ÷ 4 = 5. Discuss the meaning of the ÷ symbol as “put into sets of”. Pose similar examples using the biscuit factory scenario. With each problem encourage the students to apply any addition and multiplication fact knowledge they have to predict the result of the operation. Record each operation to consolidate meaning of the symbols.

Suitable examples might be:

Twelve biscuits shared into packets of three (12 ÷ 3 = 4)
Fourteen biscuits shared into packets of two (14 ÷ 2 = 7)
Thirty biscuits share into packets of five (30 ÷ 5 = 6)
Twenty-four biscuits shared into packets of six (24 ÷ 6 = 4)

#### Using Imaging

Shielding and Predicting: Set up problems in which the batch of biscuits is made and masked under an icecream container. Ask the students to predict how many packets of a given number can be formed. Record the operation on a post-it or piece of paper fastened to the top of the container, eg. 18 ÷ 3 =

Challenge the students to find answers using the number fact knowledge they have. For example: “If you made two packets of three, how many of the biscuits would you use?”
“What about three packets of three?”
“Can you use this to think ahead and work out how many packets can be made using 18 biscuits?”
Note that the difficult part of a skip-counting strategy is to track how many repeated
confi rm the students’ predictions.
Suitable examples might be:
10 ÷ 2 = □ 15 ÷ 3 = □ 16 ÷ 4 = □ 20 ÷ 5 = □ 60 ÷ 10 = □

#### Using Number Properties

Ask other division problems, using the biscuit company scenario, for example:
16 ÷ 2 = □ 24 ÷ 3 = □ 12 ÷ 4 = □ 30 ÷ 5 = □ 90 ÷ 10 = □
The students record the problems as division equations and solve them by applying
their strategies and number knowledge.