Ten Friends Years K - 1

Materials

• One MathMaster or MathMate per pair of children
• One Poly Plug 5x5 per pair of children

Procedure

Player B fills the empty spaces with blue plugs:

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:
   • 5 + 5 = 10 (two zig-zags)
   • 10 - 5 = 5 (cover one zig-zag)
   • 10 - 5 - 5 = 0 (cover one zig-zag then the other)
   • 2 + 2 + 2 + 2 + 2 = 10 (touch the yellow/blue pairs)
   • 5 x 2 = 10 (same way)
   • 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 = 10 (touch each plug as you count)
   • 10 x 1 = 10 (same way)
   • 3 + 3 + 2 + 2 = 10 (first 3 blues and first 3 yellows each make a triangle and the twos are the arms of the remaining cross)
   • etc.
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!