The development of anti-litter behavior in a forest campground.

The team set up a token economy in a forest campground. Kids could pick their own prizes for every piece of litter they brought back.

Researchers planted four kinds of trash and watched what happened. They let the children choose candy, toys, or other small items as pay.

Litter dropped fast once the choice system started. All four planted trash types nearly disappeared.

Letting kids pick the reward made the clean-up game work.

Burgess et al. (1971) ran the same idea one year earlier in movie theaters. They hit over 90% clean-up, a bigger swing than the campground.

Hayes et al. (1975) later swapped "choice" for "marked items." Staff pre-tagged trash and paid cash when it was returned. That tweak spread the program to streets, parks, and a zoo.

Bacon-Prue et al. (1980) moved the marked-item version into a home for adults with disabilities. Again, tokens beat trash cans and paid clean-up crews. The core rule stayed the same: show the reward, get the litter.

You can shrink litter anywhere with two steps: give a token and let the learner choose the backup prize. Camp, clinic lobby, or classroom—pick the reinforcer on the spot and watch trash vanish.