# Smiley Hundred

Purpose

In this activity students are encouraged to solve multiplication problems by deriving from known facts, looking for groupings and skip counting.  Students are encouraged to explain and share their thinking.

Achievement Objectives
NA3-2: Know basic multiplication and division facts.
Specific Learning Outcomes

model multiplication facts on a one hundred array.

use the hundreds array to find groupings, known facts to solve multiplication facts

Required Resource Materials
Smiley face grid enlarged to an A3 size and laminated

White board pen (It may also be useful for students to have a small personal copy of the grid- laminated)

Activity

1. Draw a rectangle on the grid.  Start from the top left hand corner.
Who can tell me the fact that this rectangle is about?
Did you have to count each smile to know how many groups and what size the groups were?  Why?  Why not?

2. How would we write this fact down?

Record the multiplication fact on the white board.
Can you work out the answer to this fact?

3. Ask a range of students what the answer is and how they worked it out.  Expect a range of responses.

Example

Working out what the fact is
The fact is 7 groups of 9.  You write it 7 x 9
I could see that there were 7 groups because I know that there are 5 grey smiles and 2 more.  I could see that each group had 9 in it because I know that each row has 10 and there was one less.