Juvenile literature Science 67 Experiments 50 Animals 40 Astronomy 28 Miscellanea 23 Plants 23 Biography 20 Earth 17 Weather 16 Botany 14 Electricity 14 Light 14 Physical geography 13 Rain forest animals 13 Dinosaurs 12 Birds 11 Earth science 11 Earth sciences 11 Insects 11 Water 11 Exploration 10 History 10 Sound 10 Nature 9 Planets 9 Computer network resources 8 Ocean 8 Encyclopedia 7 Juvenile 7