WA.4. Physical Science
PS1. Force and Motion
2-3.PS1. Force Makes Things Move: In prior grades students learned to use appropriate words to describe the position and motion of objects and the effects of forces on objects. In grades 2-3 students learn that forces work not only to push and pull objects, but also affect objects when they are dropped or thrown. Whenever the motion of an object changes, there is a force involved. Greater forces on a given object result in greater changes of motion. In addition to being able to describe how forces change the motion of objects, students are expected to measure the position of objects using measuring instruments such as rulers. Students can also measure time to the nearest minute. Emphasis should be on comparisons of forces and motions rather than on calculation so that students develop conceptual understanding of how forces make things move.
2-3.PS1A. Students know that motion can be described as a change in position over a period of time.
2-3.PS1A.1. Students are expected to give an example to illustrate motion as a change in position over a period of time (e.g., if a student stands near the door and then moves to his/her seat, the student is "in motion" during that time).
2-3.PS1B. Students know that there is always a force involved when something starts moving or changes its speed or direction of motion.
2-3.PS1B.1. Students are expected to identify the force that starts something moving or changes its speed or direction of motion (e.g., when a ball is thrown or when a rock is dropped).
PS3. Energy: Transfer, Transformation, and Conservation
2-3.PS3. Forms of Energy: Students learn to identify several different forms of energy. Children in this age range have an intuitive understanding of energy concepts. For example, energy is needed to get things done; humans get energy from food. It is possible to build on these ideas by having the students explore different energy phenomena.
2-3.PS3A. Students know that heat, light, motion, electricity, and sound are all forms of energy.
2-3.PS3A.3. Students are expected to explain how light, sound, and motions are all energy.