Some dinosaurs were big. How big? As long as four school buses in a row, as heavy as sixteen elephants.

Some dinosaurs were small. How small? Read and find out

Simple text and illustrations present the three states of matter, solid, liquid, and gas, and describes their attributes.

National Geographic Primary Readers is a high-interest series of beginning reading books that have been developed in consultation with education experts. The books pair magnificent National Geographic photographs with lively text by skilled children's book authors across four reading levels.