Geometry
Draw basic geometric shapes (square, triangle, rectangle, oval, rhombus, circle) on 6” cardboard squares. Pass out the shapes and challenge the children can find something on the playground with a similar shape. 
*Divide children into small groups and let them make shapes with their bodies on the grass.
Measurement
Give children rulers to measure objects on the playground. “Can you find something 2” long? Can you find something smaller than an inch? What’s longer than 5”? How can you measure the slide?”
*Give children a popsicle stick or piece of string and ask them to find something longer, shorter, the same size, etc.
Position I Spy!
Children use positional words to play “I Spy” on the playground. For example: I spy something beside the slide. I spy something behind the tree. I spy something above the sidewalk. I spy something between the big tree and the fence…
Sorting
Ask children to collect different items on the playground. (This will vary with the season and your habitat.) Put their objects together in a big pile. Ask the children to sort the objects. What was their sorting rule?
Seriation
Collect sticks of different lengths and have the children put them in order from smallest to largest.
*They could also seriate leaves, rocks, etc.
Graphing
Ask each child to find a leaf on the playground. Make a graph and have the children lay their leaf in the appropriate space. Compare quantities.