3

Light

4

Dr. Why-Physics

4

Money

2

Jack's Sack

3

Meteorites, Meteoroids, and Meteors

3

The Jeweled Frog and the Mighty Condor

3

Magnetism

4

Maddy's New York Diary

4

Maddy's Wisconsin Diary

3

The Jeweled Frog and the Mighty Condor

3

Neptune

3

Mars

3

Asteroids