Pre-Maths: Self checking colour grading game.

This is a simple game for preschool or early year students when they are practising terms like light/dark and lightest/darkest when learning about colours.

Use paint colour strips from the local DIY outlet that have shades of the same colour on the strip.
Cut in a strip half length ways.
Keep one half as it is.  Cut the other half into individual colours.

Have the child arrange the single colours from lightest to darkest (or vice versa).  Then they can check the order themselves by comparing it with the intact half.