Teacher Notes for Number Board

Number Board is a game of strategy for 2 players or two teams.

Each player has a board like a bingo card with random numbers.
10 19 17 47
35 26 40 9
24 37 3 28
6 48 15 33

Players are given access in turn to a calculator. This is faulty – only three (random) number keys are working. The player must use these digits with the standard operators to form a number on the board. The first player to get a row of 4 in any direction wins.

The game provides basic mental arithmetic practice as players calculate the alternative numbers they can make with the keys given and an opportunity to use strategies such as prioritising corner numbers (which could be part of 3 different rows).

The game may be customized for a variety of ages and abilities by varying seven parameters.

  1. Calculator type – simple or algebraic

A simple calculator provided behaves like the calculators common in primary classrooms, which means that it does not obey the rules of order of algebraic processing. Calculations are completed in order from left to right and not following the BODMAS convention. Thus 4+3x2 = 14 and not 10.

For further discussion of this issue see


  1. Number range – this gives the range of numbers available on the boards - numbers in the range 1-99 may be selected.

  1. Operators - addition and subtraction are always active, multiplication and division may additionally be selected.

  1. Must use all three digits – if set to YES a player must use all three digits shown on the calculator – the OK key will not function until all have been used - simpler versions allow children to use just a subset of the numbers provided, even a single number.

  1. Allow two digit input – if the operational keys include 3 and 5, for example, the number 35 may be entered.

  1. Display bracket keys – brackets are available for use in algebraic logic – ie operations in brackets are carried out first.

  1. Lowest value key – this may be 0, 1 or 2. There are arguments for and against using the 0 and 1 keys. If all three digits must be used zero can be useful eg 1x5+0=5.  For young children this is quite an interesting thing to do as it teaches them something about the result of adding (or subtracting) zero. They may discover that multiplying or dividing by zero is less useful. Similar arguments apply to the number 1. However, without the 0 and 1 keys more complex arithmetic may be required.

Three versions of the game with fixed settings are provided:
  Level 1 Level 2 Level 3
Calculator type simple simple algebraic
Number range 1-20 1-50 1-99
Operators + - only all all
Must use all three digits no no yes
Allow two digit input no no no
Display bracket keys no no yes
Lowest value key 1 0 0

  1. Level 1 – is suitable for the youngest KS1 children or those with special needs.
  2. Level 2 – is suitable for upper KS1 or lower KS2
  3. Level 3 – is suitable for upper KS2 or KS3.
It is also possible to set up three user options with different combinations.

Development ideas Children could make similar games to play away from the computer using 3 dice. Pencil and paper investigations might include: