ATLAST FM Released Open-Ended Items - Horizon … TA items/ATLAST … · Released Open-Ended Force and Motion Teacher Items ... Question 2: Other than giving the book a harder shove,

Released Open-Ended Force and Motion Teacher Items Horizon Research, Inc. (HRI) developed the ATLAST Force and Motion Teacher Assessment as part of a larger study. The project—Assessing Teacher Learning About Science Teaching (ATLAST)—was funded by the National Science Foundation under Grant no. EHR-0335328. Information about the ATLAST project is available at HRI’s ATLAST website: http://www.horizon-research.com/atlast. This document contains the force and motion teacher items that were developed during the process of creating the ATLAST Force & Motion Teacher Assessment. The items were developed during a months-long iterative process, and have been used with middle grades science teachers. However, there is little evidence of reliability and validity because the items were not developed in a rigorous process like the multiple choice items found on the assessments. To learn more about the item development process, please see the ATLAST Force & Motion Teacher Assessment User Manual, which can be found at the ATLAST website. Content Assessed by the Items All of the items measure understanding of the idea that “an unbalanced force acting on an object changes the object’s speed, or direction of motion, or both” (American Association for the Advancement of Science/Project 2061, 1993). In addition, the content domain was specified by “unpacking” this idea into 10 “sub-ideas,” which are shown in Table 1. Each of the released assessment items included addresses one or two specific sub-ideas.

Table 1 Force and Motion Content Domain

Idea: An unbalanced force acting on an object changes its speed or direction of motion, or both. Sub-ideas:

A. A force is a push or pull interaction between two objects, and has both magnitude and direction.

B. All of the forces acting on an object combine through vector addition into a net force; they either balance each other out (net force is zero), or act like an unbalanced force (net force is not zero).

1. If the sum of forces exerted on an object in one direction is the same strength as the sum of forces exerted on the object in the opposite direction, then the forces on the object are balanced (i.e., the net force is zero).

2. If the sum of forces exerted on an object in one direction is greater than the sum of forces exerted on the object in the opposite direction, then the forces on the object are unbalanced (i.e., the net force is not zero).

C. A force diagram uses arrows to represent the forces acting on an object at a particular moment. The length of the arrow represents the relative magnitude of the force. The direction of the arrow represents the direction of the force acting on the object.*

D. If an object is moving faster and faster, then there is a net force acting on the object in the same direction as the motion.

E. If an object is moving slower and slower, then there is a net force acting on the object in the direction opposite to the object’s motion.

F. If an unbalanced force acts on a moving object in a direction that is neither in the direction of the object’s motion, nor directly opposed to it, then the object’s direction (and possibly speed) will change.**

G. If there is an unbalanced force acting on an object, the greater the strength of the unbalanced force, the greater the change in the object’s velocity.

H. If there is an unbalanced force acting on an object, the more massive an object is, the smaller the change in the object’s velocity.

I. If an object has constant speed in a straight line (or zero speed), then there is no net force acting on the object. This can occur either when:

1. the forces on the object are balanced; or 2. there are no forces exerted on the object

J. The force of friction acts to oppose the relative motion of two objects in contact. Friction acts on both objects along the surfaces in contact with each other. The magnitude of friction depends upon the properties of the surfaces and how hard the objects are pushed together.

* This sub-idea was not assessed explicitly, but forces were represented in this way in the items. ** This sub-idea is included for completeness of unpacking, but it is not included in the assessment. Only motion

in one dimension is addressed.

Item ID: FM-OE11

Primary Sub-Idea(s) Assessed: A: A force is a push or pull interaction between two objects, and has both magnitude and direction.

You decide to take your middle school science class to the bowling alley for some “hands-on” experience with force and motion. You ask Jill to take a turn. After she releases the ball and it is rolling down the alley, you ask her to describe the force(s) that are acting on the ball at that time. Jill describes two forces:

1) The force of the ball moving forward down the alley, and 2) The force of friction that slows the ball down.

What aspects of her response, if any, are correct? What aspects of her response, if any, are incorrect?

Item ID: FM-OE24

Primary Sub-Idea(s) Assessed: A: A force is a push or pull interaction between two objects, and has both magnitude and direction. I: If an object has constant speed in a straight line (or zero speed), then there is no net force acting on the object.

This can occur either when the forces on the object are balanced, or there are no forces exerted on the object.

At the beginning of a unit on forces, Ms. Alton is leading a class discussion asking her students what they know about forces. Below is a list of the ideas brought up by her class.

I. A force is a push or pull on an object. II. The amount of force an object has depends on its size. III. Forces have both a strength and direction. IV. When two objects collide, the force of one object is transferred to the second object. V. A moving object stops when its force is used up. VI. There are no forces on an object that is not moving.

Which of these student responses would you consider to be correct? For each that is incorrect, what is incorrect about it?

Item ID: FM-OE06

Primary Sub-Idea(s) Assessed: D: If an object is moving faster and faster, then there is a net force acting on the object in the same direction as

the motion.

A teacher asks her students to identify whether the forces acting on a car accelerating onto the highway are balanced or unbalanced. The students agree that the forces acting on the car are unbalanced. What aspects of the students’ response, if any, are correct? What aspects of the students’ response, if any, are incorrect?

Item ID: FM-OE07


the motion.

A teacher shows the diagram below of a sled and all the horizontal forces acting on it to her students.

She asks them, “If the sled was not moving initially, will it start to move, and if so, how?” One student says: “Because there is a net force acting on the sled, it will move at a constant speed.” Based on this student’s response, what could the teacher do next to move this students’ thinking forward?

Item ID: FM-OE10


the motion. E: If an object is moving slower and slower, then there is a net force acting on the object in the direction opposite

to the object’s motion. J: The force of friction acts to oppose the relative motion of two objects in contact. Friction acts on both objects

along the surfaces in contact with each other. The magnitude of friction depends upon the properties of the surfaces and how hard the objects are pushed together.

Students in your middle school science classroom are working through a series of lessons that uses toy cars and rubber band launchers to shoot the cars across the floor. During one of the upcoming lessons, students will be asked to make predictions and then observe what happens when the car is placed in the launcher and then released.

Force Arrows The arrow in the diagram above is used to indicate the direction in which the car will travel. Force arrows, however, are used to represent the forces acting on an object at a particular time. Force arrows are drawn such that the length of the arrow represents the strength of the force (the longer the arrow, the greater the force) and the direction of the arrow represents the direction of the force.

Using the three cars below, draw the force arrows that identify the horizontal forces (i.e., to the left or right on the page) acting on the car at the following points of time:

1) As the car is being launched (i.e., while the car is moving but still in contact with the rubber band);

2) A few seconds after the car leaves the launcher and is no longer in contact with the rubber band; and

3) Just before the car comes to a stop. Please label the force associated with each of the arrows that you draw and indicate if the car is speeding up, traveling at a constant speed or slowing down.

1) 2) 3)

Item ID: FM-OE12


the motion. J: The force of friction acts to oppose the relative motion of two objects in contact. Friction acts on both objects


Imagine that at the beginning of a unit on Force and Motion, you are trying to understand what kinds of ideas your middle school students already have about the relationship between force and motion. Taking an old book, you place it on the floor where all the students can see it and give it a hard push with your hand. The textbook slides across the floor and eventually stops. You repeat this demonstration a couple more times and then ask the students to respond, in writing, to the following four questions. What responses would you expect middle school students to give to each of the following questions, whether correct or incorrect? Please list as many as you can, numbering them for later reference. Question 1: Why did the textbook slow down and eventually stop? Question 2: Other than giving the book a harder shove, is there any way to make the same book go farther before it stops? If so, how? If not, why not? Question 3: Can you imagine any situation where once you gave the book a shove, it never came to stop? If so, describe that situation. If not, why is such a situation not possible? Question 4: Once the book leaves the teacher’s hand, what forces (if any) act on the book? Please indicate by specifying the number(s), which of the student responses you anticipated for each question above are correct. Question 1: Question 2: Question 3: Question 4:

Item ID: FM-OE13



to the object’s motion.

After a unit on force and motion, a teacher gives his middle school students a test. One of the items is as follows:

If the forces on an object are constant and unbalanced (a non-zero net force), what can you say about the object’s motion?

Now imagine that you gave this item to your middle school students before a unit on force and motion as a way to understand what they are thinking before you begin teaching them. Write as many responses as you can imagine students giving to this question before they have studied the topic of force and motion. When you’re done, please place a check mark beside the responses that you would consider correct; i.e., the kind of response you hope students would give after the unit.

Item ID: FM-OE15


the motion. I: If an object has constant speed in a straight line (or zero speed), then there is no net force acting on the object.


Your local miniature golf course invites your middle school science class to their annual event – “The Physics of Golf.” Before beginning play, you are planning to ask each student to tell whether the forces acting on the ball are balanced or unbalanced at various points on the 1st hole – a hole that is straight and level. Describe the horizontal forces acting on the ball at key points along the ball’s path, from just before the ball is struck until the ball is at rest in the bottom of the cup (after making a “hole-in-one”).

Item ID: FM-OE16


the motion. I: If an object has constant speed in a straight line (or zero speed), then there is no net force acting on the object.


You take your middle school science class on a field trip to the Air Show. During one portion of the event, the class observes a group of skydivers jumping out of an airplane.

You ask your students to write in their journals about the vertical forces acting on a skydiver at two different points in her trip to Earth: 1) 10 seconds immediately after jumping out of the plane (while she is still accelerating), and 2) 30 seconds after opening the parachute (while she is falling toward the ground at a constant

speed). You are going to develop a scoring rubric to score the students’ responses. Outline a response that would receive the highest score in the rubric.

Item ID: FM-OE17


the motion.

At the end of a unit on Force and Motion, a middle school science teacher is creating a multiple choice test for his students. One item includes the illustration below, showing a box sliding across a floor to the right with unbalanced forces acting on it. The force acting to the right is greater than the force acting to the left.

He writes the following question, “Which of the following statements is true about the motion of the box in the picture?” He has already written the correct answer, “The box will go faster and faster as long as these are the only two forces acting on the box.” However, he is having a difficult time coming up with other response options. What other responses can you suggest? These should be ideas that you think students actually have and might choose instead of the correct answer.

Item ID: FM-OE18



to the object’s motion. I: If an object has constant speed in a straight line (or zero speed), then there is no net force acting on the object.


In a professional development workshop on Force and Motion, the facilitator displays the following student item from a statewide assessment.

Student Assessment Item

A toy is free to slide to the left or to the right on a flat, frictionless surface. Indicate the direction of the net horizontal force (to the left, to the right, or no net force) for each of the scenarios listed below: 1. The toy sits at rest. 2. The toy is moving to the right at a constant speed. 3. The toy moving to the right and speeding up. 4. The toy is moving to the right and slowing down. 5. The toy is moving to the left and slowing down. 6. The toy is moving to the left and speeding up.

The facilitator then asks you to think about how your students might respond to this problem. For each scenario, what would you consider a correct student response? For each scenario, what would be a common incorrect response by your students and why might they answer that way?

Item ID: FM-OE19




You are now planning a unit on the following big idea:

An unbalanced force acting on an object changes its speed or direction of motion, or both. You have just completed a unit on describing the motion of objects, including the concepts of speed, velocity, and acceleration. After your unit on unbalanced forces, you will move on to a unit including a study of circular motion and gravity. What are the different sub-ideas (e.g. a force is a push or a pull interaction between two objects) within this unit on unbalanced forces will you address? From the ideas that you have listed, which one idea would you expect to cause students the most difficulty? Why?

Item ID: FM-OE20


the motion.

The three questions below pertain to the following scenario. Please answer each question in the space provided.

Scenario The following is a homework question for students midway through a unit on forces and motion: Jeremy places a box on the floor and then begins to push it. The horizontal forces acting on the box are represented by the force arrows shown in the diagram. (Arrows point in the direction of the force and longer arrows represent greater forces than shorter arrows.) Describe what happens to the box from the instant Jeremy begins his push, explaining your answer.

Friction Jeremy’s Push

Write what you would accept as a complete and correct response from a middle school student. The following are responses given by three different students to the scenario on page 1. What does each response tell you about the student’s thinking on forces and motion?

Student A wrote: “Jeremy pushes on the box, but the opposite force cancels out Jeremy’s push and the box does not move at all.”

Student B wrote: “The box will start moving to the right at a constant speed because the

bigger force wins over the smaller force.” Student C wrote: “The box will move a short distance to the left and then a larger distance to

the right.”

Midway into your unit on forces and motion, the majority of your students are responding similar to Student B in Question 2 above. What would you do next in your instruction to move their understanding forward?

Item ID: FM-OE21




Read the following scenario, and then answer the question below.

Scenario You are teaching a series of lessons that uses toy cars and rubber band launchers. During one of the lessons, students are asked to make predictions and then observe what happens when the car is placed into the launcher and then launched.

After the demonstration, you ask your students to explain the forces acting on the car from the time that the car is launched until it comes to a stop. A student provides the following response:

The force of the launcher makes the car speed up. Once this force has run out, the force of friction takes over and will make the car slow down and eventually stop.

There are elements of the student’s response in the scenario above that are correct, but some elements are also ambiguous or vague. What question(s) would you ask this student to determine what the student truly understands and misunderstands?

Item ID: FM-OE22


the motion.

Read the following question from a student assessment on forces and motion, and then answer questions below.

Student Assessment Item Maria is asked by her teacher to move a file cabinet. As she pushes, the cabinet begins to move. What will happen if she keeps pushing just as hard as she did when it first started to move? A. The file cabinet will keep going at the same speed. B. The file cabinet will speed up until it gets to the speed that matches Maria’s push. C. The file cabinet will go faster and faster. D. The file cabinet will speed up until Maria’s push is used up.

The above multiple-choice question is administered to a group of middle school students. If a majority of your students select answer choice “A,” what does that tell you about their understanding of this concept? What would you do next in your work with these students?

Item ID: FM-OE23


the motion. J: The force of friction acts to oppose the relative motion of two objects in contact. Friction acts on both objects


At the beginning of a unit on forces and motion, you set up a demonstration for your students, in which a rubber band, stretched between two posts, is used to launch a toy car across the classroom floor. Following the demonstration, you ask the students to explain the forces acting on the car just after the car is released from the rubber band. Students are likely to offer a number of different answers, some correct and some incorrect. What are some incorrect answers your students are likely to give? For each incorrect idea, please explain why you think a student might have that idea. What would be a completely correct student answer?

Item ID: FM-OE25


the motion.

At the end of a unit on Force and Motion, a middle school science teacher is creating a multiple choice test for his students. He writes the item below that includes an illustration showing a box sliding across a floor to the right with two forces acting on it. The force acting to the right is greater than the force acting to the left.

Student Assessment Item Which of the following statements is true about the motion of the box in the picture?

Write a correct response option that the teacher could use for this question.

Write three incorrect response options that the teacher could use. These should be ideas that you think students actually have and might choose instead of the correct answer.

Item ID: FM-OE04

Primary Sub-Idea(s) Assessed: E: If an object is moving slower and slower, then there is a net force acting on the object in the direction opposite


As part of a demonstration, a teacher gives a box a quick push so it slides across the classroom floor. Students watch as the box moves slower and slower and eventually stops. The teacher asks students why the box moves slower and slower. A student replies: “The force you gave to the box ran out.” What aspects of this student’s response, if any, are correct? What aspects of this student’s response, if any, are incorrect?

Item ID: FM-OE05



A teacher gives her students the following question on a test at the beginning of a unit on force and motion.

Student Assessment Item Jorge is pushing a shopping cart along level ground at a constant speed. All of a sudden, the cart starts going slower and slower. Which of the following could explain why the cart moved slower and slower?

Most of the students say: “There are no longer any forces acting on the cart.” What question(s) could the teacher ask to better understand the students’ thinking about what makes objects move slower and slower?

Item ID: FM-OE08



A teacher tells her class, “A school bus moves slower and slower. Using what you have learned about forces, explain why the bus moves slower and slower.” One student says,

“The school bus moves slower and slower because the net force acting on the bus is getting smaller and smaller.”

What aspects of this student’s response, if any, are correct? What aspects of this student’s response, if any, are incorrect?

Item ID: FM-OE09



A teacher says “A school bus moves slower and slower. Using what you have learned about forces, explain why the bus moves slower and slower.” One student says,

“The school bus moves slower and slower because the net force acting on the bus is getting smaller and smaller.”

What question(s) would help the teacher diagnose this student’s understanding of why the bus is moving slower and slower?

Item ID: FM-OE26



Read the following scenario, and then answer the question below.

Scenario Midway through your unit on forces and motion, you want to evaluate how students are thinking about the relationship between forces and motion. Taking a textbook, you place it on a table and give it a push. The book slides across the table and stops. You ask Jill to describe the force(s) that are acting on the book after you have pushed it and it is sliding across the table. Jill describes two forces:

(1) The force of the book moving across the table, and (2) The force of friction that slows the book down.

What aspects of Jill’s response, if any, are correct? What aspects of her response, if any, are incorrect? What question(s) would you ask Jill to better understand her thinking about this concept?

Item ID: FM-OE03

Primary Sub-Idea(s) Assessed:

A teacher describes the following situation to his students. “Two identical hockey pucks move toward each other with equal speed across a level frictionless surface as shown in Diagram #1. (Note that the arrows in this question indicate the path of motion, not the forces on the pucks.) Puck Y collides with Puck X as shown in Diagram #2, and Puck Y stops.”

The teacher asks his students to draw a diagram that illustrates the path of Puck X after the collision. Write what you would accept as a complete and correct response from a middle school student.

Item ID: FM-OE01

Primary Sub-Idea(s) Assessed: I: If an object has constant speed in a straight line (or zero speed), then there is no net force acting on the object.


A teacher hangs a block from a string so that it is not moving, and asks students to identify the forces acting on the block. Brad responds that there are two forces: the force of gravity acting downward, and the force of the string pulling upward. Molly disagrees, stating that there must not be any forces acting because the block is not moving. What could the teacher ask the students to do in order to help them further their thinking about the relationship between force and motion?

Item ID: FM-OE02



In a science lesson on forces, the teacher directs the class to observe a textbook sitting on a desk. The teacher then asks the students to write in their science journals a response to the question, “What forces are acting on the book?” One student says: “Gravity is pulling the book downward, but the desk is pushing upward with equal strength.” What aspects of this student’s response, if any, are correct? What aspects of this student’s response, if any, are incorrect?

Item ID: FM-OE14



As students are getting settled for class one day, a middle school science teacher who you are mentoring puts a drawing on the board like the one at the right. It shows an object and all the forces acting on the object.

The fact that all arrows are the same length and pointing in opposite directions means that the forces are balanced; i.e., the forces to the left and right are equal to each other, and the up and down forces on the object are equal. To see how well students understand the force ideas she has been teaching the last few days, the teacher asks her students to individually write statements that could describe the motion of the object. Every student in the class writes essentially the same thing,

“Because all the forces are balanced, they cancel each other out. Since they cancel each other out, the object must not be moving at all.”

The teacher shows you the students’ papers later in the day and asks you if she should feel comfortable moving on to the next topic. What, if anything, would you tell the teacher that these students still need to understand?

Item ID: FM-OE27



You include the following multiple-choice question on a pre-test that you give students prior to a unit on forces and motion. Read the student question, and then answer the question below.

Student Assessment Item Your science textbook is sitting on your desk. Which of the following diagrams describes the forces on the book? (The arrows in the diagrams are force arrows. Force arrows point in the direction of the force and longer arrows represent greater forces than shorter arrows.)

A.

Force due to gravity

B. Force of the

desk on the book


C. Force of the desk onthe book


D. Force of the desk on the book


E. There are no forces acting on the book since it is not moving.

Which one of the answers to the student pre-test question above indicates that a student has a correct understanding of the situation? Which answer choice are your students most likely to pick on the pre-test? What would a student’s selection of this answer choice tell you about his/her thinking about this concept?

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ATLAST FM Released Open-Ended Items - Horizon … TA items/ATLAST … · Released Open-Ended Force and Motion Teacher Items ... Question 2: Other than giving the book a harder shove,