1. Earth

11 questions

average score: 70% (all users)

2. Jupiter

12 questions

average score: 69% (all users)

3. Mars

10 questions

4. Neptune

8 questions

5. Saturn

11 questions

average score: 42% (all users)

6. The Planet Mercury

10 questions

7. Uranus

9 questions

8. Venus

10 questions