Ten Friends

Years K - 1


Children love to play this easy-to-state, easy-to-start game based on a ten frame. It involves children in predicting and checking addition facts to ten. Discussion is important and calculators are used to make a symbolic record of what is created. Children often want to extend the challenge for themselves. Suitable for threading.


  • One calculator per pair
  • One Poly Plug per pair
  • One spot dice per pair
Playing Ten Friends

Note: This investigation has been included in Maths At Home. In this form it has fresh context and purpose and, in some cases, additional resources. Maths At Home activity plans encourage independent investigation through guided 'homework', or, for the teacher, can be an outline of a class investigation.
  • Visit the Home Page for more Background.
  • For this specific activity click the Learners link and on that page use Ctrl F (Cmd F on Mac) to search the task name.


Remove two rows of plugs from the red board so the rows are side by side.
This makes a Poly Plug 10 Frame.
Ten Board
  • Player A rolls the dice and leaves it where it lands...
  • then places that number of yellow plugs into the gaps in any way...
  • and writes on the calculator the number placed [5].
Alternatively, leave out the third step for now and bring in calculator recording later as below.
Ten Board showing 5
Player B has to 'look hard' at the empty spaces and tell their guess of the number of blue plugs it will take to fill the gaps, saying I think I need...

Then they check their guess by counting blue plugs into the spaces...

and complete an equation on the calculator to make ten, in this case 5 [+] [5] [=] 10.
Complement of 5 to make 10


Listed alphabetically.
Primary content in bold.
  • 1:1 correspondence
  • addition facts beyond 10
  • addition facts to 10
  • complementary addition
  • conservation of number
  • counting
  • estimating number
  • group counting
  • mathematical conversation
  • place value
  • problem solving
  • recording - calculator
  • recording - written
  • subitising
  • visual & kinaesthetic representation of number
Alternatively, Player B may tell their guess then write the equation first to show they know the Ten Friend. However, a mathematician always checks things another way, so they now count in the blue plugs to confirm.

Once a hypothesis has been checked, players swap roles and play another round. They will want to continue for many rounds.

It seems teachers get excited about the activity too. These two responses appeared in the email almost immediately following a Working Mathematically with Infants workshop presented for the Mathematical Association of Victoria. You might want to find out more about our Professional Development programs.

Hi Doug,
Many of our teachers were enthusiastic after the PD. The prep team are very excited about making bug catchers.
(see Aaron Peeters article below). David, one of our teachers trialled Ten Friends with his grade using glue stick holders and reversible counters.
Sarah, Yarraville West Primary School
Hi Douglas,
Ten Friends was awesome today. I teach Year 2s and, for some, this is knowledge that they have and they are able to readily explain their understandings. Having said that they were fully engaged and 'having a great time.' The questioning and discussions were really informative. Going to begin 'threading' this activity tomorrow.
Very excited!!!!!!!!
Carole Hall, Point Cook P-9 College

Look! We Have Made...

If you choose to play the game without the calculator as a running record, then when a hypothesis has been made and checked by counting in, the children exclaim to each other: Look! We have made seven plus three equals ten. or whatever. They know which number was plugged first, because the dice hasn't moved. Then the plugs are removed and the game starts over swapping the roles of roller and guesser.

(Note: The exclamation Look! is considered important to re-focus attention on the whole that has been created.)

When appropriate, using the question: Would you like to write that on your calculator? or Would you like to write that on your calculator like a mathematician?, encourages using the calculator to record that verbal statement. This form of recording is quicker than written recording and adds visual and kinaesthetic components to the symbols representing the numbers and operation being spoken.

However, at another appropriate time, encourage written recording using the question: Would you like to draw a picture of that? or Would you like to write that like a mathematician might do it?. Ill-formed numerals will be part of this experience and a question like: That's a great seven you have drawn. Is it the same as the one on the calculator? helps children identify the differences and challenge themselves to try again. You also have the opportunity to ask: Would you like me to help your hand write it the way a mathematician would?

Touch & Tell

Also, sometimes, every Ten Friend situation is a potential discussion starter. Not every time because we don't want the flow and fun of the game to be lost by 'teaching too hard'.

Use a completed board to generate more equations. This can be done sitting with a pair, or by using one of the children's boards as the focus of a teaching group discussion.

At the simplest level, expect children to 'touch and tell' number stories like those below. Later, expect the children to write equations which can be justified by touching the plugs in the frame. Plugs are not moved. For example, in the finished picture above you might see:

  • 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)
  • ...


  1. See this activity used in a buddy situation in this Snapshot from Alexandra Primary School.
  2. Choose a finished board such as 6 + 4 =10 and ask children to explore and record all the ways they can arrange the plugs to still 'say' 6 + 4 =10.
    • How many arrangements are there?
    • How do you know when you have found them all?
    Recording can simply be spots of yellow and blue in two rows of five on scrap paper, or you might design a record sheet. In either case, model the recording you want.
  3. Children soon begin exploring with more rows of plugs removed. Perhaps they will need two dice per pair.
  4. How about starting with ten plugs in the frame? Player A rolls to remove. Player B has to guess the number that's left and check by counting out.
    • How do the children tell each other about what they have done now?
    • How do they record it? On paper? On the calculator?
  5. Four red boards make 100 gaps!

Why did Aaron Peeters, Warburton Campus, Ngaanyatjarra Lands Schools, Western Australia make these Ten Friends houses? Find the answer in his story Learning to be Flexible with Numbers to 10 (PDF).

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