Dr Alvin Silverstein, Dr Virginia Silverstein, Laura Silverstein Nunn
Library Binding
(Enslow Pub Inc, Dec. 1, 2010)
Hundreds of years ago, people used to just toss their trash right out their back doors. Modern people have invented lots of ways to keep things clean—but we still have to deal with pollution problems like smog, litter, and oil spills. Learn about things that make our planet dirty in this great addition to the YUCKY SCIENCE series.