We did a scavenger hunt at the park on Monday. I printed 3 copies of a list of 10 items and taped the lists to 3 gallon-size plastic bags. Then my kids and my nephew looked for the stuff while we walked around the walking trail. They all enjoyed that. I had: pine cone, acorn, yellow leaf, green leaf, brown leaf, red leaf, gumball (from a tree), interesting stick, rock. Plus I told them they'd get a bonus if they found something else cool in nature (that was NOT trash--or poop).