"A Planet Full of Plastic: and how you can help” - by Neal Layton.
We found a very easy to read book about the environment & ecology for children. Found it while we were browsing through a bookstore in London. Our son loved it; he was very much engaged and had questions. The book itself is tailored for primary school children but can be for older children too. It was even great for adults! What I found was especially good was that the book not only talks about the issues with plastic but also talks about suggestions of what we can do about it.