Brief description: Primates must use tools to get sticky food out of the bottom of containers
Materials: containers with narrow mouths (so chimpanzees cannot fit their whole hand in)
Assembly instructions: None required
How to use: Using a knife, smear a sticky treat like peanut butter into the bottom of containers. Provide tools such as chopsticks so the chimpanzees can reach the treat.
Price: None if using recycled containers.