"Explains the principles of inventing and provides photo-illustrated instructions for making a variety of structures and contraptions"--Provided by publisher. Interest Level: 3-6 Reading Level: 6.0 Lexile Measure: 740 Lexile Code: IG (Illustrated Guide) Guided Reading Level: Q Recommended for use in science lessons by NSTA. Teaching Books: https://school.teachingbooks.net/tb.cgi?tid=38466.