Mary Ann Bonnell & Kirk Johnson 
Trees Are Made Of Gas [PDF ebook] 

See-oh-too is an influential guy. Trees Are Made of Gas teaches young readers all about carbon dioxide, an invisible, odorless gas that is essential for plant growth-but is also responsible for global climate change. Kids learn both the science and impact of the massive release of carbon dioxide into the atmosphere, making a clear argument for conservation and clean up. Providing simple explanations along with ways to reduce your own carbon footprint, this engaging book is sure to engage young environmentalists.