Lesson Plan Template: Learning Cycle (5E Model)
Learning Objectives: What will students know and be able to do as a result of this lesson?
Students will explain Newton's Three Laws of Motion.
Students will evaluate why Newton's Laws of Motion are important to understand.
Students will calculate mass, net force, and acceleration using Newton's Second Law of Motion.
Students will apply Newton's Three Laws of Motion to explain various real-world situations.
Students will explain the meaning of Newton's First and Second Laws of Motion through the reading and comprehension of a text excerpt.
Students will create a product with a writing component to explain Newton's Three Laws of Motion and evaluate why they are important to understand; this argument will be coherent and will integrate correct vocabulary terms and information gathered from reading sources throughout the lesson.
Prior Knowledge: What prior knowledge should students have for this lesson?
Students should know how to use a balance to measure mass (either triple-beam or digital).
Students should know how to convert between units within the metric system.
Students should know how to correctly produce a scatter plot. Students should know how to use scientific notation when dividing and multiplying.
Students should know how to use the equations of motion to calculate initial and final velocity, distance, and acceleration.
Students should understand how to apply the Scientific Method.
Guiding Questions: What are the guiding questions for this lesson?
- What are Newton's Three Laws of Motion?
- Two astronauts are playing catch in space. One of them misses a throw. Describe the motion of the ball after the astronaut misses the catch.
- A soccer ball is kicked; it comes to rest after rolling through the grass. Why is this not considered a violation of Newton's First Law?
- How can Newton's Second Law of Motion be used to explain why it is more difficult to push a large truck than it is to push a small car?
- How can Newton's Third Law of Motion be used to explain why it is difficult to walk on a slippery surface, such as ice?
- Why are Newton's Three Laws of Motion important to understand?
Sample Answers to Guiding Questions:
- Newton's First Law: An object in motion stays in motion unless acted upon by an outside force; Newton's Second Law: A net force produces an acceleration which is in the same direction as the net force (F = ma); Newton's Third Law: For every force there is another force that is equal in magnitude and opposite in direction.
- After the astronaut misses the ball, the ball will continue moving in a straight line forever, or until it interacts with an outside force (such as the gravitational field of another planet or star).
- The soccer ball is under the influence of a net external force - the force due to friction between the ball and the grass.
- A large truck has more mass and therefore requires proportionally more force to accelerate than a small car (F=ma). You can also explain this using Newton's First Law: the truck has more mass and therefore has more inertia, meaning it has greater resistance to changes in its motion.
- When walking, you push backwards with your foot. It is the reaction force of friction (which points in the opposite direction - forward) which propels you forward. If the surface is slippery, then there is less friction and thus a smaller maximum reaction force, meaning that it is more difficult to walk forward.
- Newton's Three Laws are important to understand because they describe the interaction and motion of objects in a fundamental manner. Most basic motions of macroscopic objects can be explained and described using Newton's Three Laws of Motion.
Engage: What object, event, or questions will the teacher use to trigger the students' curiosity and engage them in the concepts?
Begin the class by showing one of the following animations, followed by a short discussion. Any of the videos could be easily placed into a PowerPoint presentation:
Car Hits a Brick Wall
Truck Hits a Car, Ladder Keeps Moving
Car Crash Test, No Seatbelt
Do a Think-Pair-Share activity with the following question:
You are watching an ice hockey game. You notice that the players are able to keep moving even when they stop pushing off with their skates. How is this possible? What would need to happen in order to stop the skater?
In a Think-Pair-Share, each student first thinks about the question individually (they may write their answer down on paper). After that, they discuss their ideas with the student sitting next to them. Finally, there is a class discussion on the topic in which students share their ideas and defend their points to the class.
Answer to Engage question:
The players have inertia, which is an object's resistance to changes in its motion. Once the hockey player is moving, he will keep moving in a straight line at a constant speed until acted upon by an outside force.
Explore: What will the students do to explore the concepts and skills being developed through the lesson?
Inertial Balance Lab
Students explore the concept of Inertia using an inertial balance. They collect data points to find the mass and period squared of seven objects. They create a plot of this data and from this plot predict the mass of an unknown object. At the end of the lab, students are introduced to the concept of inertia and use it to explain how the Inertial Balance works and whether the balance could be used in space.
It is recommended that before students perform the lab, the teacher has the lab stations prepared for the students. The Inertial Balances should be clamped to the tables with a large C clamp and the appropriate number of masses should be placed at each station. If using a triple-beam balance, the teacher should review how to use the balance to ensure proper data collection. It is important that the teacher demonstrates proper use of the Inertial Balance, as students will have a tendency to pull the balance back too far and disrupt the calibration of the balances.
The students are expected to complete the following during the lab:
- Write a hypothesis
- Create a data table
- Collect data
- Perform calculations
- Create a scatter plot
- Answer analysis questions
- Write a conclusion
Explain: What will the students and teacher do so students have opportunities to clarify their ideas, reach a conclusion or generalization, and communicate what they know to others?
Webquest and Demonstration
Students complete a Webquest to reinforce understanding of Newton's First and Second Laws as well as Free-body diagrams. While completing the Webquest, students answer questions on the student handouts found below and take written notes.
It is recommended that students use headphones during Part I of the Webquest, as there is a short video for them to watch. However, if headphones are unavailable, students can watch the video at a low volume.
Student Handouts for Parts I-III
Answer Keys for Parts I-III
Demonstration for Newton's Third Law:
For this demonstration, you will need two rolling chairs and a whiteboard (or projector on which you can make drawings).
- Begin by having two students sit in the rolling chairs facing each other. Have the students push off of each other's hands (so that they move away from each other).
- You then draw the two students on the board and label all forces (normal force, gravity, friction, push by the student, push from other student) on each student. Have students draw as you draw.
- After the initial drawing, you can also have the students draw a free body diagram to go with their drawings.
- On the drawings, the direction of the student's acceleration should be indicated. Point out to students that the direction of acceleration is the same direction as the push by the other student, not the push given by the accelerating student.
- Ask the class why the rolling students eventually slowed down and stopped in order to review Newton's First Law.
- Have a student sit on a rolling chair facing a wall. The student then pushes off the wall and rolls away.
- Again, draw the student and all forces. Have the students suggest forces instead of telling them the forces.
- It is likely that the students will not include push from wall, such that in the end, you have "push by student" and "acceleration of student" pointing in opposite directions.
- At this point, review Newton's Second Law. Ask the students what is providing the force of the acceleration.
- The students should come to the conclusion that the wall is providing the missing force. Use this to define Newton's Third Law for students.
- Point out that the harder the student pushes, the harder the wall pushes back and thus the faster the student accelerates.
- The following animation may be helpful to further demonstrate Newton's Third Law: Man Steps Off of Boat
- Begin by asking the class how they are able to move forward while walking. Which way do you push with your foot while walking?
- Draw a diagram of a foot pushing off to walk. Ask students which forces are acting on the foot - they will likely list Normal Force, Gravity, and Push by Foot
- Have students apply Newton's Second and Third Laws to determine which force will push the foot forward. If students are having trouble, ask them why it is difficult to walk on a slippery surface.
You may find the following presentation helpful when conducting the demonstrations: Newton's Third Law Demonstration Notes
Elaborate: What will the students do to apply their conceptual understanding and skills to solve a problem, make a decision, perform a task, or make sense of new knowledge?
In order to practice calculations for Newton's Second Law and completing Free Body Diagrams, students complete the following worksheet:
For more extended practice with all three laws, students could complete the following inquiry activity:
Balloon Rocket Cars - Newton's Laws Practice
Balloon Rocket Cars - Analysis Questions Answer Key
The first option focuses on calculations and can be completed independently by students. The second option is an extended inquiry activity. Students are provided with the following materials: balloon, cardboard, straws, lifesavers, tape. They are then instructed to build a car that will reach the greatest distance possible. Students explain the motion of the cars and justify their designs using Newton's Laws of motion.
Both options could be used, to deepen both conceptual and mathematical understanding, time permitting.
For the inquiry lab, groups of 3-4 work best. If both options are employed, then this section should take approximately 3-4 class periods (about 3-4 hours).
During both activities, the teacher should circulate to answer questions and make suggestions. After students complete the worksheet, the teacher could either collect the worksheets and grade them or provide the students with solutions so that they may review their work and self-grade their papers.
Newton's Laws Project
Students will complete a project to demonstrate mastery of Newton's Three Laws of Motion. In the assignment as written, students are given the option of either: writing a letter to Sir Isaac Newton, recording an original song, or creating an original poster. Creativity in the project should be encouraged. When assigning this project in the past, the option of students coming up with their own project assignment has been left open (for instance, one student created a Newton's Laws themed board game).
If the teacher desires, the options can be limited, with the option of writing a letter being the most straightforward and traditional to complete. However, the songs that students have created for this project in the past have helped them to remember the laws much more vividly, and this option should be encouraged if possible.
If the teacher wishes to focus on the writing standards, then the letter should be assigned, as it is the most formal and most directly assesses student mastery of the standard. However, all three projects have a writing component of some sort.
The teacher will gather formative assessment data throughout this lesson.
During the engage section, the teacher will gather diagnostic assessment information by monitoring student discussion of the introductory question. In this way, the teacher can assess the general level of understanding of the principles underlying Newton's First Law.
During the Explore section, the teacher should circulate among lab groups to monitor for proper procedure and for understanding. During this time the teacher may ask questions such as:
- What will happen to the motion of the balance as more mass is added? Why?
- Do you think this experiment would work the same way on Mars (or in space)? Why or why not?
- When students are done collecting data: Why do you think the Period is longer for an increased mass?
Sample answers to formative assessment questions in the Explore section:
- The balance should slow down (or have a longer period) as more mass is added. It will be more difficult for the balance to make the turns when it has additional mass.
- Yes, because the inertial balance does not rely on gravity, but rather its internal springs. It should work the same way anywhere in the Universe.
- The period is longer for increased mass because the added mass makes it more difficult for the inertial balance to make the turns.
The teacher can also collect the students' lab reports to check for student understanding formally by grading the lab reports.
The Explain section is student-centered. Students will be answering various questions as they read about the principles of Newton's Laws. The teacher will receive direct feedback through the Google Form responses from the students.
The demonstration portion of the Explain section (for Newton's Third Law) also gives the teacher a chance to review student understanding of the first two laws and free-body diagrams. The teacher can thus generally assess student understanding by asking the questions suggested in the body of the lesson.
Students will either complete a lab or a worksheet (or both) for the Elaborate section. The teacher can monitor students as they complete these activities to check for understanding through informal conversations.
Feedback to Students
Students will receive feedback from the Explore section if the teacher collects and grades the lab report. They will also receive informal feedback through conversations with the teacher as the experiment is performed.
During the Explain section, the students will again receive verbal feedback from the teacher, who will circulate and monitor informally. They will receive direct instruction at the end of the Explain section, which will also allow for general feedback.
If the students complete the worksheet for the Elaborate section, then the teacher may grade the worksheets to give students formal written feedback. The teacher could also provide the student with an answer key when the worksheet is completed so that the student may self-correct, with the teacher's support as necessary.