Investigating Forces and Motion
The purpose of this unit plan is to guide students in exploring the relationship between force, mass, and motion by analyzing data, applying mathematical reasoning to calculate speed and kinetic energy, and explaining how these factors interact to influence an object’s movement. They will build and compare various catapults throughout the unit.
Overview
Students investigate how an object's motion depends on net force and mass in a middle school unit built around catapults. They open with projectile videos, identify variables, and build a popsicle-stick catapult. In the exploration, they use two PhET projectile simulations and roll balls of different masses down a ramp to gather data. Mini lessons then cover energy transfer, Newton's second law, and projectile motion. Students build a catapult from several options, launch water balloons three times, and use a data sheet to calculate speed, kinetic energy, acceleration, and force. They answer claim-evidence-reasoning questions and present through a choice board. The plan is scheduled day by day across twelve days, beginning with two 50-minute sessions on Days 1-2.
Lesson Objectives
- Describe how the change in an object’s motion depends on the sum of the forces acting on the object and the mass of the object.
- Gather and analyze data to support their conclusions about motion and forces.
- Apply mathematical reasoning to calculate speed and kinetic energy.
- Explain the relationship between mass, speed, and kinetic energy.
Standards
NGSS · 3
- MS-PS3-1Construct and interpret graphical displays of data to describe the relationships of kinetic energy to the mass of an object and to the speed of an object.
- MS-PS3-5Construct, use, and present arguments to support the claim that when the kinetic energy of an object changes, energy is transferred to or from the object.
- MS-PS2-2Plan an investigation to provide evidence that the change in an object’s motion depends on the sum of the forces on the object and the mass of the object.
CCSS Math · 3
- 6.EE.B.6Use variables to represent numbers and write expressions when solving a real-world or mathematical problem; understand that a variable can represent an unknown number, or, depending on the purpose at hand, any number in a specified set.
- 6.EE.B.7Solve real-world and mathematical problems by writing and solving equations of the form x + p = q and px = q for cases in which p, q and x are all nonnegative rational numbers.
- 7.EE.B.4Use variables to represent quantities in a real-world or mathematical problem, and construct simple equations and inequalities to solve problems by reasoning about the quantities.
CCSS ELA · 2
- RST.6-8.3Follow precisely a multistep procedure when carrying out experiments, taking measurements, or performing technical tasks.
- RST.6-8.1Cite specific textual evidence to support analysis of science and technical texts.