 | I Wonder Why Stars Twinkle and other questions about space | Paperback |
 | I Wonder Why Castles Had Moats and other questions about long ago | Paperback |
 | I Wonder Why the Wind Blows and other questions about our planet | Paperback |
 | I Wonder Why Venetians Walk on Water and other questions about people and places | Paperback |
 | I Wonder Why Kangaroos Have Pouches and other questions about baby animals | Paperback |
 | I Wonder Why Snakes Shed Their Skin and other questions about reptiles | Paperback |
 | I Wonder Why Greeks Built Temples and other questions about Ancient Greece | Paperback |
 | I Wonder Why Trees Have Leaves and other questions about plants | Paperback |
 | Rocks and Minerals | Paperback |
 | Jerozolima I Ziemia Święta | Paperback |
 | Kanada | Paperback |
 | I Wonder Why Stalactites Hang Down and other questions about caves | Paperback |
 | Grandes construcciones | Paperback |
 | I Wonder Why There's a Hole in the Sky and Other Questions About the Environment | Paperback |
