How can containers keep stuff from warming up or cooling down?

This 6th grade science unit on thermal energy builds toward the following NGSS Performance Expectations (PEs):

• MS-PS1-4*: Develop a model that predicts and describes changes in particle motion, temperature, and state of a pure substance when thermal energy is added or removed.
• MS-PS3-3: Apply scientific principles to design, construct, and test a device that either minimizes or maximizes thermal energy transfer
• MS-PS3-4: Plan an investigation to determine the relationships among the energy transferred, the type of matter, the mass, and the change in the average kinetic energy of the particles as measured by the temperature of the sample
• MS-PS3-5: Construct, use, and present arguments to support the claim that when the kinetic energy of an object changes, energy is transferred to or from the object.
• MS-PS4-2*: Develop and use a model to describe that waves are reflected, absorbed, or transmitted through various materials.
• MS-ETS1-4: Develop a model to generate data for iterative testing and modification of a proposed object, tool, or process such that an optimal design can be achieved.

*These performance expectations are developed across multiple units. This unit reinforces or works toward these NGSS PEs that students should have previously developed or will develop more fully in future units. In the OpenSciEd Scope and Sequence, PS4-2 is first built in Unit 6.1. In this new context of particle models and energy transfer, students learn more about how absorption of light occurs at the particle level. This unit begins to address changes in state that are part of PS1-4; then changes in state are more fully developed in the next unit, 6.3, on water cycling. In 6.3, students learn that evaporation and condensation occur when energy is added or removed from the substance.

The 6th grade science unit on thermal energy expands students’ understanding of particle models and energy transfer, which include these Grade 6–8 DCI elements:

PS1.A: Structure and Properties of Matter

• Gases and liquids are made of molecules or inert atoms that are moving about relative to each other. (MS‑PS1‑4)
• In a liquid, the molecules are constantly in contact with others; in a gas, they are widely spaced except when they happen to collide. In a solid, atoms are closely spaced and may vibrate in position but do not change relative locations. (MS‑PS1‑4)
• The changes of state that occur with variations in temperature or pressure can be described and predicted using these models of matter. (MS‑PS1‑4)

PS3.A: Definitions of Energy

• The term “heat” as used in everyday language refers both to thermal energy (the motion of atoms or molecules within a substance) and the transfer of that thermal energy from one object to another. In science, heat is used only for this second meaning; it refers to the energy transferred due to the temperature difference between two objects. (secondary to MS‑PS1‑4)
• Temperature is not a measure of energy; the relationship between the temperature and the total energy of a system depends on the types, states, and amounts of matter present. (secondary to MS‑PS1‑4)
• Temperature is a measure of the average kinetic energy of particles of matter. The relationship between the temperature and the total energy of a system depends on the types, states, and amounts of matter present. (MS‑PS3‑3), (MS‑PS3‑4)

PS3.B: Conservation of Energy and Energy Transfer

• When the kinetic energy of an object changes, there is inevitably some other change in energy at the same time. (MS‑PS3‑5)
• The amount of energy transfer needed to change the temperature of a matter sample by a given amount depends on the nature of the matter, the size of the sample, and the environment. (MS‑PS3‑4)
• Energy is spontaneously transferred out of hotter regions or objects and into colder ones. (MS‑PS3‑3)

PS4.B: Electromagnetic Radiation

• When light shines on an object, it is reflected, absorbed, or transmitted through the object, depending on the object’s material and the frequency (color) of the light. (MS‑PS4‑2)

ETS1.A: Defining and Delimiting an Engineering Problem

• The more precisely a design task’s criteria and constraints can be defined, the more likely it is that the designed solution will be successful. Specification of constraints includes consideration of scientific principles and other relevant knowledge that is likely to limit possible solutions. (secondary to MS‑PS3‑3)

ETS1.B: Developing Possible Solutions

• A solution needs to be tested and then modified on the basis of the test results in order to improve it. There are systematic processes for evaluating solutions with respect to how well they meet the criteria and constraints of a problem. (secondary to MS‑PS3‑3)

*There is a strike through part of the DCI elements that are not developed in this unit. In the OpenSciEd Scope and Sequence, students will develop an understanding of changes in state, particularly as they relate to pressure, in OpenSciEd Unit 6.3, and frequency (color) of light in OpenSciEd Unit 8.4. The placement of this OpenSciEd Unit 6.2 and associated units are shown in the OpenSciEd Scope and Sequence. 

• Developing & Using Models
• Planning & Carrying Out Investigations
• Analyzing & Interpreting Data
• Constructing Explanations & Designing Solutions
• Engaging in Argument from Evidence

• Systems & System Models
• Energy & Matter
• Structure & Function

Beginning in Lesson 4 and throughout the unit, students focus on pooling and then averaging test results and building an understanding of temperature as a measure of average particle movement. They take measurements in the tenth or hundredth in decimal points, and must consider negative and positive numbers as they mass systems. Prerequisite math concepts that may be helpful include:

• CCSS.Math.Content.5.NBT.A.3 Read, write, and compare decimals to thousandths.
• CCSS.Math.Content.5.NBT.A.4 Use place value understanding to round decimals to any place.
• CCSS.Math.Content.6.SP.A.3 Recognize that a measure of center for a numerical data set summarizes all of its values with a single number, while a measure of variation describes how its values vary with a single number.
• CCSS.MATH.CONTENT.6.NS.C.5 Understand that positive and negative numbers are used together to describe quantities having opposite directions or values (e.g., temperature above/below zero, elevation above/below sea level, debits/credits, positive/negative electric charge); use positive and negative numbers to represent quantities in real-world contexts, explaining the meaning of 0 in each situation.

Calculating a mean of a data set is a target idea in 6th-grade CCMS. Prior to Lesson 4 in this unit, talk to your grade’s math teacher to find out when students will learn how to calculate the mean of a numerical data set in math class this year. If they have worked on this already, ask the math teacher for an example data set they worked with and any suggested modification to your anchor chart for calculating a mean. If students haven’t yet worked through any examples in their math classes, then the pooled temperature data in this lesson will be an example you save to refer to in future lessons in concert with this anchor chart. Also ask the math teacher if students have worked with using negative numbers to represent quantities in the real world. This will inform your decision about how to represent temperature changes in the pooled class data table.

This is the second unit in 6th grade in the OpenSciEd Middle School Scope and Sequence and it focuses on thermal energy. Given this placement, several modifications would need to be made if teaching this unit earlier or later in the middle school curriculum. These include:

• If taught before OpenSciEd Unit 6.1, supplemental teaching of light interactions with matter, such as reflection and transmission, would need to be added. These ideas are fundamental to the model students need to build of energy transfer through particle collisions.
• If taught before OpenSciEd Unit 6.1 or at the start of the school year, supplemental teaching of classroom norms, setting up the Driving Question Board, and asking open-ended and testable questions would need to be added. (These supports are built into 6.1.)
• If taught later in the OpenSciEd sequence after other engineering design challenges, modify the cup design challenge so that students are more involved in defining the problem and determining the criteria and constraints. Currently, Unit 6.2 is students’ first introduction to engineering design in the OpenSciEd 6–8th grade sequence. Therefore it is more scaffolded than it would need to be if the unit were taught much later in the middle school curriculum.

• Lindsey Mohan, Unit Lead, BSCS Science Learning
• Zoe Buck Bracey, Writer, BSCS Science Learning
• Emily Harris, Writer, BSCS Science Learning
• Ari Jamshidi, Writer, Stanford University
• Abe Lo, Writer, BSCS Science Learning
• Michael Novak, Writer & Reviewer, Northwestern University
• Tracey Ramirez, Writer, Charles A. Center at UT-Austin
• Dawn Novak, Pilot teacher, Maple School 
• Tyler Scaletta, Pilot teacher, North Shore Country Day School
• Katie Van Horne, Assessment Specialist
• David Fortus, Unit Advisory Chair, Weizmann Institute of Science

BSCS Science Learning

• Kate Herman, Copyeditor, Independent Contractor
• Stacey Luce, Editorial Production Lead
• Valerie Maltese, Marketing Specialist & Project Coordinator
• Alyssa Markle, Project Coordinator
• Chris Moraine, Multimedia Graphic Designer

This unit was adapted from Energy: How can we design a device to warm something up?, originally co-developed by San Francisco Unified School District and SCALE at Stanford University 2017–2018. Used with permission. Energy: How can we design a device to warm something up? was developed with funding from Lucas Education Research, part of the George Lucas Education Foundation.

An integral component of OpenSciEd’s development process is external validation of alignment to the Next Generation Science Standards by NextGenScience’s Science Peer Review Panel using the EQuIP Rubric for Science. We are proud that this unit has earned the highest score available and has been awarded the NGSS Design Badge. You can find additional information about the EQuIP rubric and the peer review process at the nextgenscience.org website.