Children are naturally resourceful. Spend an afternoon in the park with no toys or equipment and they'll gather sticks, rocks and leaves to play with. The next time you go for a nature walk have them collect all the interesting treasures they see and challenge them to create nature faces like the ones we saw on Makes and Takes.
See more examples as well as some guidance in Heather Mann's post on Makes and Takes.
Also, check out the work of Italian painter Giuseppe Arcimboldo for inspiration. Arcimboldo was an artist known for his portraits made frompainted fruits, vegetables, flowers and the like. Check out some of the more whimsical pieces by Arcimboldo and see if you and your child can identify the individual items used to create each portrait.