Introduction: Create a 3 x 3 grid and use each number from 1 to 9 just once to fill each grid space, so each line adds to 15. It is all
created with natural objects that can be moved around. 15 is the magic number every row and column can total for a 3 x 3 grid, when the numbers 1-9 are only used once. An activity to problem solve and think in numbers all in one.

Instructions:

  1. Use the sticks to create a grid 3 x 3 in size. Chalk on
    the floor could also be used. Same dimensions as
    a noughts and crosses board.
  2. Find nine different natural items like pebbles,
    feather, pine cones, seeds. Just 1 object is
    needed for the first item(e.g. 1 feather), then 2
    items for the second item (e.g. 2 leaves), then 3
    items for the third (e.g. 3 twigs) etc up to 9 items.
    This will be 45 items in total.
  3. Start with just one row. Can you select three
    different items, one for each section of the grid
    row, so that they total 15 when counting every
    item in the row.
  4. Now add items to the remaining grid squares so
    every row and column add up to 15. Move all the
    items around until the problem is solved,
    including the original row if necessary.
Activity Sheet
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