This 2 page worksheet with complete teacher's answer key makes it easy to integrate math into your astronomy lesson. Students put Kepler's Laws into their own words and apply simple formulas to given values for the 8 planets to test his 3rd law of planetary motion. Then, they are asked to analyze how accurate his 3rd law is mathematically. The second page includes research on 3 dwarf planets and asks students to test Kepler's 3rd law using the data they find online for these celestial bodies. Combining Math & Science!!!