Leaf patterns to laser cut, super back to school project for kids!

I used recycled corrugated cardboard and tempera paint for this kid's project.

Daub paint with a piece of recycled plastic bag, dabbing paint like decorative sponge or rag painting techniques for walls. Plastic or Styrofoam plates hold paint colors well. Be careful of sharp edges: so finger painting is no recommended for corrugated cardboard.
Finger painting might be safe for laser cut cereal boxes (chipboard food packaging) or poster board.

Also, have children write their name on the back before you paint so they can get their leaf back when you change classroom decorations.
I used a tip from Buzzfeed.com "37 Teacher Hacks" to hang the leaves. Put a strip of blue painter's tape on the wall, put a line of hot glue on the blue painter's tape and stick your leaf up.

Humidity will create some warping over time. Hey, it's just cardboard...