Recycling or trading books constitutes the “in thing” for Earth Day in one of the schools where I substitute teach.  The youngsters and teachers bring  used books to the school where they are sorted by grade level.
Then each child can select a book or books to take home, the number depending on how many are received in each age group.   This is one way to recycle books and provide great reading for youngsters and teachers.
What other activities are you involved in for Earth Day…as parents,  a family, home schooling parents, or at your school?