| title | ISBN-13 | year of publication |
|---|---|---|
| Eyes: Thematic unit | 978-0-7877-0004-1 | 1994 |
| Feathers: Thematic unit | 978-0-7877-0005-8 | 1994 |
| Gears and Wheels Thematic Unit | 978-0-7877-0006-5 | 1992 |
| Incredible Human Body | 978-0-7877-0036-2 | 1995 |
| Life in a Pond | 978-0-7877-0304-2 | 1997 |
| Life in the Desert | 978-0-7877-0037-9 | 1995 |
| Light | 978-0-7877-0046-1 | 1996 |