An experimental analysis of anti-litter procedures.

The team tested four ways to stop litter in two movie theaters. They tried extra trash cans, warning signs, a short film, and a kid-friendly token plan. Kids could trade collected litter for candy, soda, or toys right away.

Each method ran on different days. Staff counted litter before and after shows. The token plan was the only one that paid kids for results.

The token plan removed over 90% of litter. Trash cans, signs, and the film barely helped. Kids worked fast because the reward was immediate and sure.

The result stayed strong across both theaters. No other trick came close.

Clark et al. (1972) copied the idea in a forest campground. They let kids pick their own prizes. Litter still dropped fast, showing the theater trick travels outdoors.

Hayes et al. (1975) made the job even easier. They pre-marked litter and paid only for those pieces. Their marked-item method kept 55–88% of litter off the ground with less staff work. It builds on Burgess et al. (1971) by trimming the time adults spend watching.

Bacon-Prue et al. (1980) moved the same marked-item plan into a home for adults with intellectual disability. Tokens plus a dollar and a photo on the wall beat both trash cans and paid clean-up crews. The 1971 kid trick works for adults too.

You now have a cheap, fast tool that beats passive fixes like signs or extra bins. Pick a small, clear target, deliver the reward on the spot, and watch the litter disappear. Try it Monday at your clinic picnic, school fair, or park outing—just bring a bag of tokens and a few favorite snacks.