Force and Motion: Newton's Second Law

Contributor
Wayne County RESA (regional educational service agency)
Type Category
Instructional Materials Assessment Materials
Types
Instructor Guide/Manual , Lesson/Lesson Plan , Activity , Assessment Item
Note
This resource, vetted by NSTA curators, is provided to teachers along with suggested modifications to make it more in line with the vision of the NGSS. While not considered to be “fully aligned,” the resources and expert recommendations provide teachers with concrete examples and expert guidance using the EQuIP rubric to adapted existing resources. Read more here.

Reviews

Description

This resource is a Word document comprising a 5-E lesson sequence about the relationship between force, mass and motion. Components include activities, a video clip, a reading with interactive questions, designing and running an experiment, and discourse. A student handout is available as a separate PDF document. To access this resource, go to the above URL and scroll down to the lesson called “Force and Motion - Grade 8 (B. Johnson). Click on that link to download the Word document.

Intended Audience

Educator and learner
Educational Level
  • Grade 8
  • Middle School
Language
English
Access Restrictions

Free access - The right to view and/or download material without financial, registration, or excessive advertising barriers.

Performance Expectations

MS-PS2-2 Plan 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.

Clarification Statement: Emphasis is on balanced (Newton’s First Law) and unbalanced forces in a system, qualitative comparisons of forces, mass and changes in motion (Newton’s Second Law), frame of reference, and specification of units.

Assessment Boundary: Assessment is limited to forces and changes in motion in one-dimension in an inertial reference frame and to change in one variable at a time. Assessment does not include the use of trigonometry.

This resource is explicitly designed to build towards this performance expectation.

Comments about Including the Performance Expectation
This lesson sequence was purposely designed to address the performance expectation. After some preliminary experiences, students plan (and run) their own investigation into the relationship between force, mass and motion. Acceleration is not measured directly, but may be inferred from gathered measurements.

Science and Engineering Practices

This resource is explicitly designed to build towards this science and engineering practice.

Comments about Including the Science and Engineering Practice
During the “elaborate” phase of the lesson, student groups choose from limited materials to design and run an experiment to determine how changing the mass and the force affect the acceleration of an object. The lesson plan reminds teachers that the students’ resulting lab report or write-up will need to include identification of independent and dependent variables, at least 3 controls explained, and a description of materials and procedure.

Disciplinary Core Ideas

This resource is explicitly designed to build towards this disciplinary core idea.

Comments about Including the Disciplinary Core Idea
The activities in the “Explore” portion of this lesson have students compare the motions of objects when either force or mass is changed (but not both). The “Explain” portion grounds students’ observations with a video clip and reading with interactive questions, designed to introduce Newton’s 2nd Law of Motion. The experiment in the “Elaborate” portion has students design experiments to test their conception of how the Law works. This lesson sequence does not directly address the idea of multiple forces acting simultaneously (the sum of forces), nor ideas about why some objects don’t accelerate and sometimes don’t even move (sum of forces is zero). To fully address this Disciplinary Core Idea, teachers will need to address these ideas with students, with an exploration of balanced vs. unbalanced forces and/or Newton’s First Law of Motion.

Crosscutting Concepts

This resource appears to be designed to build towards this crosscutting concept, though the resource developer has not explicitly stated so.

Comments about Including the Crosscutting Concept
Although the lesson does not overtly use the language of cause and effect, the concept itself is implicit in that students observe how a cause (a change in either mass or force) results in an effect (a change in motion). Students use this cause-effect relationship to predict phenomena by forming hypotheses which they will later test. A teacher will need to point out to students the cause-effect relationships that they are investigating, and that these relationships are forming the basis for the students’ predictions. The writer of this lesson plan sequence states that the cross-cutting concept of Stability and Change is addressed. This may be because the Performance Indicator links to that concept. The lesson sequence itself does not specifically address the 6-8 practices within Stability and Change.

Resource Quality

  • Alignment to the Dimensions of the NGSS: This lesson sequence seamlessly blends the Disciplinary Core Idea with the Practice of planning and carrying out an investigation. With a little targeted vocabulary on the teacher’s part, the Cross-cutting Concept about cause and effect relationships will easily be brought from the background to the fore. The sequence of lessons fit together coherently and build appropriately on one another. This lesson sequence does not foster connections to different science disciplines, except in the optional extension offered for student who have extra time.

  • Instructional Supports: Students are exposed to phenomena through a variety of media (activity, video, lesson with interactive questions) in order to make sense of a phenomenon - the relationship between mass, force, and motion. The lesson begins with an assessment of students’ prior knowledge and beliefs, and the teacher is encouraged to examine this data, though no suggestions are given about how to modify the lessons based on types of data received. Students have multiple opportunities to practice scientific discourse, as well as scientific communication through informal and formal writing as well as mathematically. The lesson sequence does not offer guidance about differentiation beyond a note to get students with reading difficulties “set up with assistive technology”. A teacher would need to develop his/her own plan for differentiation during the activity. Scaffolds could be offered to some students for the writing portions. The lab could be made more open-ended for higher level students by offering more materials, or having students come up with their own materials. The lesson sequence does include an extension activity for students who finish early, involving linking Newton’s 2nd Law to an Earth Science or biological science phenomenon.

  • Monitoring Student Progress: The lesson sequence offers multiple opportunities to show learning using a variety of different formats. The lesson plan includes a chart listing each skill with its related assessment instrument(s). The teacher is given guiding questions to use as informal formative assessments during group work. A pre-assessment activity is linked to a post-assessment activity. The assessment components relate directly to the Disciplinary Core Idea and the Scientific Practice, but not to the Cross-Cutting Concept. The teacher may assess students’ understanding of the cause and effect relationship through their writing, especially the hypotheses for their lab, and by asking probing questions throughout the investigation.

  • Quality of Technological Interactivity: The lesson plan itself is non-interactive. The lesson does include use of an internet-based video clip and an internet-based reading with interactive questions. The lesson plan also recommends use of a document camera for students to share their work with the class, and allows but specifically does not require the use of graphing software.