This is a lot of fun with younger children.
Grab a pail, big cup anything our child can put their collect in. Then head out on a walk even around the yard let them pick up what they want leaves, rocks, acorns, flowers, and anything else they want.
When done go sit on a sidewalk, front porch and go through what they collected. Count together how many items they found, name each item, talk about them, go over the colors of the items and so on.