Look for: a hypothesis that addresses how changes in th…

Look for the following in students’ notebooks (Hypotheses and Variables and Data Table and Procedure):

a hypothesis that addresses how changes in the distance between two magnets (cause) will result in differences in the amount of energy transferred to the cart (effect) when it is released

distance (gap) between the two magnets identified as the independent variable

speed of the cart after it is released identified as the dependent variable.

a data table with recorded measurements of distance traveled and travel time from when the cart is released to when it stops moving

a data table organized to record more than one value for the independent variable

a data table organized to record more than one trial for the value of the independent variable tested

calculation of average speeds for each trial or averaged speeds across multiple trials for each value of the independent variable tested

Look for the following in Making Sense of Your Investigation Results:

In response to question 1

changing the distance between the magnets causes a change in the amount of energy transfer in the field between them.

a statement saying whether this supports or refutes their initial hypothesis

In response to question 2

potential energy was stored in the magnetic field between the two magnets.

In response to question 3

a statement saying that the evidence supports the claim

reasoning that explains that the evidence shows that changing gap distance affects how loud a sound is produced when magnets are released to come back together

additional reasoning (optional) that explains that since loudness is based on the amplitude of vibration and bigger-amplitude vibrations require or carry more energy, the change in the distance must have transferred a different amount of energy into the production of the sound

Leave feedback in the form of noticings and wonderings in the student notebooks, and return these to students at the start of the next lesson. Examples of such feedback include statements like these:

I noticed you mentioned differences in energy transfer in response to question 1. I am wondering if this supports or refutes your hypothesis and why.

I noticed you discussed changes in the forces you felt in both systems as you pushed the cart into or toward the launcher. I am wondering which part of the system feels most like a spring. What evidence do you have that this part of the system could be storing potential energy as a spring does?

Additional Lesson 7 Teacher Guidance

SUPPORTING STUDENTS IN MAKING CONNECTIONS IN ELA

CCSS.ELA-LITERACY.W.8.1 Write arguments to support claims with clear reasons and relevant evidence.

In this lesson, students make a written claim about energy transfer between objects in a magnetic field and the magnetic field. They should support claims with logically organized evidence from their investigation. Students will also evaluate the reasonableness of another written claim based on sufficiency and accuracy of the available evidence.

Students’ ability to make and justify claims is supported by the procedures of this lesson. Small groups of students develop hypotheses and investigation procedures for testing their hypotheses, including determining how and what type of data to collect. In this way, they are thinking about what kind of evidence and reasoning will support or refute their hypotheses which describe cause-effect relationships.

In their ELA classes, students have experience in determining claims, evidence, reasoning, and counterclaims made by authors in reading materials and in organizing written arguments based on their understanding of complex text. They may know how to use an argument template to make a claim followed by supporting evidence and reasoning, counterclaims or rebuttals, and a conclusion.

If students are struggling to make or support claims, help them clarify their thinking by asking open-ended questions such as these:

What patterns in data do you notice?

What interactions did you notice?

What do you understand from the data you collected?

How do your data support or refute your hypothesis?

What cause-effect relationships are evident?

How is all the evidence and reasoning tied together?

Why is the claim important?

SUPPORTING STUDENTS IN MAKING CONNECTIONS IN MATH

CCSS.MATH.8.F.B.4: Construct a function to model a linear relationship between two quantities. Determine the rate of change and initial value of the function from a description of a relationship or from two (x, y) values, including reading these from a table or from a graph. Interpret the rate of change and initial value of a linear function in terms of the situation it models, and in terms of its graph or a table of values.

In this lesson, students will determine the rate of change from tabular data recorded during their investigation. They will calculate and interpret this rate as the speed of a cart moving along a track. As they analyze their calculations, it is important for students to realize that as the initial gap between magnets increases, the resulting speed of the cart decreases.

• A common error in rate (speed in this case) calculation is made when students incorrectly apply an algorithm. It may be helpful to ask them to describe the expected units to help them determine how to correctly set up their problem.
• Performing calculations by hand with decimal numerals can also lead to errors. Students can use calculators to determine cart speed since this math concept is not important to understanding the scientific principles in this lesson.