Forces and Motion
Students begin by deﬁning motion in relation to a reference point. They infer the relationships among force, speed, and mass. Speciﬁcally, they use the effect of gravity to show how force can cause motion and how it relates to mass.
Learn by Reading
For additional content-area reading, check out the Houghton Mifflin Science eBook: Grade 2, Unit F, pages 8–11 and 14–15.