Reading Metrics
Grade Level
Middle Grades (MG 4-8)
Book Level
6.6
Points
2.0
Fiction/Nonfiction
Nonfiction
Word Count
14168
Points per Word
0.000141
Page Count
31
Points per Page
0.064516
Description
Provides instructions for making such devices as a tin-can telegraph, crystal radio, and kaleidoscope, and suggests a variety of related experiments and other activities.