Newton's 3rd Law, Day 2

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Students will be able to identify action and reaction forces for a pair of objects by labeling them on a diagram and identify which object will have a greater acceleration.

Big Idea

Students apply Newton's 3rd Law and action & reaction forces in different situations.

Student Video Share-Out

20 minutes

The goal of this lesson is for students to get more practice with Newton's Third Law by identifying action and reaction forces in various situations through videos and picture examples. By the end of the class, students will have found their own examples and have applied the third law to any situation.

To start out class, I have students share some of the videos that they came up with and how they related to Newton's 3rd law by leading the class through the questions that they answered about each video (Student Videos). In the previous class, students learned about Newton's 3rd law and action reaction forces. They applied them by looking up YouTube videos that showed the 3rd law and they share them out to the class to start out class. I tell the class that I will be randomly selecting groups to present a video. I have about 6-7 groups present a video by pulling it up on YouTube so it shows on the projector screen. After each video, I ask the groups that are in the audience to take a minute or two to write down the answers to the Newton’s Third Law Video Example questions. Then I have the presenters state what the action and reaction forces are, which force is greater and which object has a greater acceleration. Students in the audience give me a Thumbs Up or Thumbs Down if they got all of the answers correct. Students continue to present until 6-7 groups have presented. The goal of this activity is for students to recall what they learned in the previous class and apply what they know about the 3rd law to various real-life situations.

Some YouTube clips that students have shown are below. Students choose a small segment of each video to show students. I ask that students show parts of the video where they do not explain how it related to Newton's third law so that the audience can determine the answers to those questions.

Newton's 3rd Law Around the Room Activity

30 minutes

After the students have shared their video examples, I give them another opportunity to practice identifying action and reaction forces with an around the room activity. I have students work in pairs for this activity with the person sitting next to them. To complete this activity, students get 2 minutes with each N3 Law Practice card. Each table gets one card at a time with two pairs looking at each situation. Students complete the N3 Partner Activity by drawing a picture and labeling forces for the situation and answering questions about action and reaction forces, which force is greater and which object has a greater acceleration. When the time is up students pass the card to the next table until they have finished all of the 10 situations. I ask that the students switch off each card who is the writer so that both partners have equal practice and buy-in for the activity that should look like this Student Work. When they complete the activity, I show the key so they can check their own papers with the correct answers. 

Newton's 3rd Law End of Discussion Checkpoint

5 minutes

When students have had sufficient practice with the video and around the room activity, they complete the End of Discussion Checkpoint #3. I have them complete this individually so that students can show what they know and can do on their own. I do not collect this checkpoint because it is so close to the test and I want students to know where the stand on the Newton's Third Law material before they leave class. Instead, I have students complete the checkpoint and flip it over at their desk when they have finished. This checkpoint is of a truck pulling a baby tree out of the ground. I tell students to answer the questions about the baby tree and the truck.

When all students are done, I ask for student volunteers to answer each question and have them check their own work. After they have checked their work, I ask students to give me a Thumbs Up or Thumbs Down on how they did on the checkpoint so I can get a visual of how well they understand the checkpoint. In this lesson, I notice that students have Thumbs Up overall. In addition, I am walking around as students are working; it is evident that they understand the idea of Newton's 3rd law.

Last Look at Learning Targets for Unit 3

10 minutes

To end the unit, I ask students to take out their Unit 3 Learning Targets. Students choose the shape they would like to use for their last look at the learning targets. They take about couple of minutes to look through their learning targets and rate themselves based on how they feel now that we have learned everything for the unit.

When all of the students complete the task, I ask them to identify 1-2 targets that they feel they need to work on before the test next class. I ask them focus on those few targets on the review sheet and in their own study time before the test. I have the students keep the learning target sheets so they can study from them in class and at home. 

Review Sheet

5 minutes

In the last few minutes of class, I hand out the Chapter 3 Review Sheet. Students can use this in addition to their learning targets to help them study for the test in the next lesson. I remind students that they can find the answer key to check their work on my classroom website. I provide them with this review sheet to help them focus their studying.