Predict A Count
Years 2 - 8

The learner plays this game with the calculator ... An adult is needed to help introduce the activity.


  • One calculator per child (there's one on your phone)
  • Maths journal or sheets of working paper that can be collected into a folio of dated work.

Getting Started

When used as described, this is one of the most powerful calculator activities we know. Once learnt, it needs to be used for 15-20 minutes, at least three times a week for several weeks. Any assisting adult should try very hard to let the calculator do the correcting, rather than telling the child their prediction is wrong.
Even for older learners it is best to begin by asking:
How can we teach the calculator to count forward by 10?
Explore the children's responses. Following the discussion, which will quickly lead to agreement to press the buttons [+] [1] [0] [=] ask the child to clear their calculator and write the screen number (which should now be zero) at the top of their working paper.

The learner then guesses the next number the calculator will show if we use it to count by 10 and writes their guess on their paper under the zero.

After writing the guess they check on the calculator by pressing [+] [1] [0] [=].

  • If their guess was correct, they tick their work.
  • If their guess was wrong, they put a line through their error and write the correct number beside it.
Whether ticked or corrected this is a now piece of data in the pattern that will develop.

The process of guess/write/check/correct continues as far as the child can go.

  • There is no need to intervene once you have done the first five or so together, ie: 0, 10, 20, 30, 40, 50, ...
  • It is important that the child is encouraged to continue beyond the numbers they may normally use.
  • When a problem develops, encourage the child to look back at their correct guesses to establish clues for the next guess.

Learning From Experience

Quite often with this example, the first time the calculator contradicts the learner is the next count after 100. Children often predict it is 200.

Let the calculator do the correcting. Then they put a line through the 200 and write 110 as the calculator has written. Your role is to encourage the learner to look back at the developing pattern and encourage them to use that information to predict the one after 110 and then keep going.

Keep insisting that they only need to make a guess - the calculator will tell them if their guess is right or wrong. This private reinforcement and correction is very powerful. Insisting on writing the guess, and ticking and crossing it, is a vital management strategy. It is particularly useful if a child pushes the wrong buttons (which they will know) or accidentally clears their calculator. After consultation you need only suggest the child re-enters the last correct response, teaches the calculator to count again, and continues.

Have fun exploring Predict A Count.

These photos are from Bradley, Year 2. In the first week of school he learnt Predict A Count using the example above. What the teacher didn't know was that he loved it so much he kept working on it at home. In the second week of school he brought in 13 pages of Predict A Count to show the new teacher what he had done. The left photo shows the first page where he continued counting from 580, which was where he got up to at school. Notice that at the end of this page he successful 'crosses over' 1000. The right photo shows that he went as far as 10,000.

There are more ideas in the Answers & Discussion.

Just Before You Finish

Sometimes when time is up for this activity ask the child to look back at the data and see what they notice. Then they record a sentence or two about what they notice. If the child is very young, you write what they say.
  • Use the Working Like A Mathematician page to frame your conversation with the child. For example:
    Mathematician's make predictions like that too. They say they are making a hypothesis. You must be working just like a mathematician.
    Mathematicians love it when they find a pattern like that. Well done. That means you are working like a mathematician.


It is the variations based on the mathematician's question What happens if ...? which make this activity so adaptable to a wide range of ages - even adults.
  1. What happens if we alter the starting number. Make it as hard as you can for yourself.
  2. What happens if we alter the size of the counting group. I'll bet you couldn't count by 05s today.
  3. What happens if we count backwards using subtraction. How could you teach the calculator to count backwards?
  4. What happens if we choose our own starting number and group counting number and whether to count forwards or backwards.
  5. What happens if we choose a decimal starting number and count by a decimal.


Answers & Discussion

These notes were originally written for teachers. We have included them to support parents to help their child learn from Predict A Count.

Send any comments or photos about this activity and we can start a gallery here.


Maths At Home is a division of Mathematics Centre