This is the second and final part of a review of educational research on children’s ideas about gravity. The
first part concerned students’ understanding of how and why things fall. This article picks up the trail of
research studies that address students’ understanding of the more complex ideas of projectile motion and
orbits and examines how the recommendations of national education standards fare in light of this body of
research. The article begins with a brief historical sketch of how these ideas developed in human history
and a summary of the relevant Benchmarks and Standards