Momentum and Its Conservation: Understanding Check

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Students will able to demonstrate an understanding of momentum, its conservation and kinetic energy for different systems.

Big Idea

Mathematical models of momentum and its conservation are useful when predicting the motion of massive objects.


The goal of this lesson is to help students use each other's strengths to construct explanations for concepts that relate to momentum and its conservation. This lesson addresses the HSA-SSE.A.1 and HS-PS2-2 standards because it asks students to use their notes and collaborate with team members to create a study guide on momentum, its conservation, and kinetic energy. I also ask questions on concepts from previous units to assess students' ability to retain information across units.  This lesson aligns with the NGSS Practices of Developing and Using Models (SP2), Analyzing and Interpreting Data, Using Constructing Explanations (SP6) and Obtaining, Interpreting and Communicating Information (SP8) for Science because students will use their prior knowledge to explain factors that are related to both the momentum and kinetic energy of an object in motion.

Within this lesson, students demonstrate their understanding of the key terms that relate to the momentum of on an object on a practice understanding check. Students apply the G.I.R.L.S. protocol to at least eight problems of their choice from this unit and create a single note sheet that they can use while taking their understanding check. Students then collaborate with their peers to rank and revisit problems from their notes to correct any misconceptions that students at their table may have. Finally, students complete the understanding check using their note sheet, a calculator, and a writing utensil. Within this lesson, I ask students to focus on deepening their current understanding of momentum and its conservation. I assess student understanding throughout the lesson using an understanding check, and grade each student's work at the end of the school day on a scale of 1 (Advanced Beginner) to 5 (Highly Proficient).


5 minutes

The portion of the lesson follows a routine to communicate the ideas that students need to be proficient in by the end of the semester and it also highlights the goals of the lesson to students. I summarize the key ideas through the bell-ringer activity and take attendance while students transfer the information into their notebooks.

Today's additional piece of information is a BIG IDEA which states that mathematical models of momentum and its conservation are useful when predicting the motion of massive objects. Later on within this lesson I ask students to use the "sage on the stage" protocol to create study guides that students use during today's understanding check.  In this lesson, I want students to get ready to use collaboration and consider multiple viewpoints on a the concepts of momentum and its conservation. After students create study guides, I assess their understanding of momentum and its conservation using an understanding check. 

Review: Kinetic Energy, Momentum and It's Conservation

30 minutes

In this section of the lesson, students spend twenty minutes individually creating a study guide that shows how to answer questions from the Practice Understanding Check using the G.I.R.L.S. protocol and other helpful hints on how to handle problems that relate to momentum and its conservation.  Students take a piece of card stock and fold it lengthwise once and twice width-wise to create 8 equal windows. In each window, students write the solution to a problem of their choice using the G.I.R.L.S. protocol. 

After each student creates a study guide, students spend ten minutes conferencing with their table mates to help push through any challenges in their understanding. For the next ten minutes, students work together to use a strategy I call the Sage on The Stage.  At each table, students spend a minute to rank eight questions from least challenging to most challenging. Students then work together for the last nine minutes to annotate their solution guide to reflect changes that the student expert(s) at their table suggest. Click here to see an example of students using this strategy. Click here to see an example of students work. Students will use this study guide during an understanding check.  

Understanding Check: Momentum and Its Conservation

40 minutes

During this section of the lesson, students use their user guides, a calculator, and a writing utensil to take an assessment on their understanding of the difference between momentum and its conservation for different scenarios. Students sit in groups of four at lab tables with a four-way table divider. I choose an understanding check where students are allowed a single sheet of notes because at this point in the semester students should be able to synthesize information from multiple sources and apply that knowledge to solve real-world problems. I consider this strategy to be a successful one because ~80% of students demonstrated proficiency (83.5% or higher) on this understanding check. 

I take final questions from the whole class and then distribute the understanding checks to each student. I turn the "How are we learning arrow to individual" and students spend thirty minutes completing the assessment. I project a message on the interactive whiteboard at the front of the room that tells students good luck and has a timer embedded in it. Students spend the next thirty minutes completing the understanding check on momentum and its conservation.


5 minutes

To wrap up this section of the lesson, I ask students to look at the Minds on Physics modules that I post on the class Edmodo wall for homework. This set of modules asks students to analyze explosions using Newton's third law, ideas from momentum change and impulse principles to predict the relative force, acceleration and momentum changes of interacting objects. I choose this activity because I want students to learn about momentum and its conservation in the context of explosions, not just collisions which are our main focus in class.

I also ask students to share their medal success codes with me by midnight on Thursday morning to meet the HW deadline. Today's module asks students to interpret physics word problems to either predict the acceleration of an object or determine the magnitude of individual forces. Each module has a progress bar and a success bar. As students answer questions correctly their progress bar goes up. If students begin to answer questions incorrectly their health bar decreases. If a student's health bar reaches zero before completing the module they will have to attempt the module again. The content remains constant, but the questions change either in order or phrasing each time a student attempts a module. Once student progress reaches 100% on a module, each student receives a medal success code.

If a student demonstrates mastery with little to no evidence of stumbling, he or she receives a gold medal success code. If a student reaches mastery but stumbles in one or two instances, he or she receives a silver medal success code. Students who receive a silver medal success code are given the opportunity to continue practicing and can attain a gold medal success code. Students record these alphanumeric codes on a record-keeping sheet which correspond to either gold or silver medals on a Minds on Physics module. I give students with gold medals credit for being highly proficient on a standard and students with silver medals credit for being proficient on a standard on our digital grade book