The mayor went to the Northerly Island to attend the Chicago Conservation Corps graduation ceremony.
Some of the students entertained him and other guests at the graduation. Daley said saving the environment can save money.
"If you keep your school clean, you don't have to hire all the janitors to keep it clean. Just think, it saves you money, and that money stays in your school. So if you recycle, you make sure your lockers are clean, your desk, all the things that go into it, we don't have to spend an enormous amount of money cleaning inside and outside the school," said Daley.
The mayor added that conservation is everyone's responsibility.