You can order a free class set of the popular Can Clan-textbook (in Danish).
The textbook about Chad Clan and his recycling friends provides children with solid insight on what recycling bottles and cans means and why it is important.
The textbook is divided into short chapters on specific themes with easy-to-read texts, fun facts and student projects. In addition, the book has a cartoon series on the same theme as the text that is suitable for the youngest students or those who are not yet strong readers.
You can get a free set of books for your class and read an online version of the book here.