Ten Friends

Years K - 1

Materials

Procedure

Playing Ten Friends Remove two rows of plugs from the red board so the rows are side by side.

Ten Board

Player A places a number of yellow plugs into the gaps in any way, eg:

Ten Board showing 5

and writes on the MathMate the number placed [5].
Note: the number to be placed may be decided by the roll of a dice.

Player B fills the empty spaces with blue plugs:

Complement of 5 to make 10

  and completes an equation on the MathMate to make ten ... [5] [+] [5] [=] 10.
Or Player B may write the required number on their MathMate without calculation and show it to Player B as an hypothesis of what is needed to make the Ten Friend.

In either approach, the hypothesis is checked by 'counting in' - counting as you plug in - the blue plugs.

Variations

  1. Sometimes use a completed ten to generate equations. At the simplest level, expect children to 'touch and tell' number stories like those below. Later, expect the children to write twenty equations which can be justified by touching the plugs in the frame. Plugs are not moved. For example, in the finished picture above:
  2. Children can explore all the ways they can arrange the plugs to make a particular equation such as 6 + 4 =10.
    - How many arrangements are there?
    - How do you know when you have found them all?
  3. Children soon begin exploring with more rows of plugs removed.
  4. Four red boards make 100 gaps!
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