Five Facts

There are several scaffolds for the five facts.

1. Using the Ten Facts

One strategy builds on student’s knowledge of the times ten facts. The five facts are half of the corresponding 10 fact. 6 X 5 is half of 6 X 10. This is more effective for even multiples. For facts like 7 X 5, some students think

7 x 10 = 70

7 X 5 is half of that

But they then have trouble mentally finding half of 70. When faced with an odd five fact, some programs have students find the immediately lower five fact, and then add 5.

For example, for 7 X 5,

6 X 5 is half 6 X 10, or 60
half of 60 is 30
add 5 to get 35.

I find this a little procedural for my tastes – I’d rather work on student’s skills for finding half of numbers like 30, 50, or 70. This is a specific skill that will be useful later anyway.

2. Using a Clock

Another scaffold is to use a clock as a scaffold. A clock automatically groups minutes into groups of 5, and therefore demonstrated the 5 X facts and connects to time. For example, when the minute hand points to 2, it shows us 2 groups of 5 = 10 minutes after the hour.

A good activity is to cut out hand outlines and use them to show groups of five around the clock. The AMDSB media centre has a hand die that can be used to make the hand cutouts.

Using 10 Strategy Cards

These cards show students the x10 facts and visually why the x5 fact is half of that.

Clock Fact Flash Cards

These cards show students a clock face with the minute hand as a visual connection to the facts.

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