To help my students learn to find points on a coordinate plane, I used a shower curtain liner. I put black electrical tape on the liner to represent the X-axis and Y-axis. Then I drew in the other lines using a black marker and a meter-stick. (For an average-sized liner, putting the lines about 15 cm apart worked well.)
I numbered the lines with a different colored marker.
After a discussion about how to find a point on the grid, place the liner on the floor. Select a student to stand on the origin (0,0), as you display a set of coordinates. The student then walks across the X-axis, and then up or down to locate the point. The class watches, and must agree whether or not the student is standing on the right point.