How to teach coordinates

Grade 4 to Grade 6

Coordinates pinpoint a location on a grid using an ordered pair of numbers, such as (3, 2). The first number is how far across (the x axis), the second is how far up (the y axis). The two axes cross at the origin, (0, 0). Getting the order right, across before up, is the whole skill at this level.

How to teach it

1. Start with a grid where only the lines are numbered, and plot points where lines cross, not in the squares.
2. Teach the order with a phrase like 'along the corridor, then up the stairs': the x value first, then the y.
3. Always begin counting from the origin (0, 0) for every point.
4. Practise both directions: read the coordinates of a marked point, and plot a point from a given pair.
5. Extend to all four quadrants with negative coordinates, and to simple shapes and reflections, once the first quadrant is secure.

Common mistakes

• Reversing the pair and plotting (3, 2) as 2 across and 3 up.
• Counting the squares instead of the grid lines.
• Starting the count from somewhere other than the origin.
• Muddling which axis is x and which is y.