There's something fishy going on in the lake at Camp Dakota . . . and it sure isn't the fish!

The campers have discovered some smelly, green gunk in the water. Yuck! The creek seems to be the source of the pollution, but how can they stop it? And why is a trash-covered duck leading them on a wild goose chase?

Look in the back of the book for experiments and more to help you become a science detective too!