U n c o v e r i n g S t u d e n t I d e a s i n S c i e n c e

P h y s i c a l S c i e n c e A s s e s s m e n t P r o b e s

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The Mitten ProblemSarah’s science class is investigating heat energy. Th ey wonder what would happen

to the temperature reading on a ther-

mometer if they put the ther-

mometer inside a mitten.

Sarah’s group obtained two

thermometers and a mitten.

Th ey put one thermometer

inside the mitten and the

other thermometer on the ta-

ble next to the mitten. An hour

later they compared the readings on

the two thermometers. Th e temperature in-

side the room remained the same during their experiment.

What do you think Sarah’s group will discover from their investigation? Circle the

response that best matches your thinking.

A Th e thermometer inside the mitten will have a lower temperature reading than the

thermometer on the table.

B Th e thermometer inside the mitten will have a higher temperature reading than

the thermometer on the table.

C Both thermometers will have the same temperature reading.

Describe your thinking. Provide an explanation for your answer.

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Practice 6 Constructing Explanations and Designing Solutions The goal of science is to construct explanations for the causes of phenomena. Students are expected to construct their own explanations, as well as apply standard explanations they learn about from their teachers or reading. The Framework states the following about explanation:

“The goal of science is the construction of theories that provide explanatory accounts of the world. A theory becomes accepted when it has multiple lines of empirical evidence and greater explanatory power of phenomena than previous theories.”

An explanation includes a claim that relates how a variable or variables relate to another variable or a set of variables. A claim is often made in response to a question and in the process of answering the question, scientists often design investigations to generate data. The goal of engineering is to solve problems. Designing solutions to problems is a systematic process that involves defining the problem, then generating, testing, and improving solutions. This practice is described in the Framework as follows.

Asking students to demonstrate their own understanding of the implications of a scientific idea by developing their own explanations of phenomena, whether based on observations they have made or models they have developed, engages them in an essential part of the process by which conceptual change can occur. In engineering, the goal is a design rather than an explanation. The process of developing a design is iterative and systematic, as is the process of developing an explanation or a theory in science. Engineers’  activities,  however,  have  elements  that  are  distinct  from  those  of  scientists.  These elements include specifying constraints and criteria for desired qualities of the solution, developing a design plan, producing and testing models or prototypes, selecting among alternative design features to optimize the achievement of design criteria, and refining design ideas based on the performance of a prototype or simulation. (NRC Framework, 2012, p. 68-69)

Grades K-2 Grades 3-5 Grades 6-8 Grades 9-12 Constructing explanations and designing solutions in K–2 builds on prior experiences and progresses to the use of evidence and ideas in constructing evidence-based accounts of natural phenomena and designing solutions. x Make observations

(firsthand or from media) to construct an evidence-based account for natural phenomena.

x Use tools and/or materials to design and/or build a device that solves a specific problem or a solution to a specific problem.

x Generate and/or compare multiple solutions to a problem.

Constructing explanations and designing solutions in 3–5 builds on K–2 experiences and progresses to the use of evidence in constructing explanations that specify variables that describe and predict phenomena and in designing multiple solutions to design problems. x Construct an

explanation of observed relationships (e.g., the distribution of plants in the back yard).

x Use evidence (e.g., measurements, observations, patterns) to construct or support an explanation or design a solution to a problem.

x Identify the evidence that supports particular points in an explanation.

x Apply scientific ideas to solve design problems.

x Generate and compare multiple solutions to a problem based on how

Constructing explanations and designing solutions in 6–8 builds on K–5 experiences and progresses to include constructing explanations and designing solutions supported by multiple sources of evidence consistent with scientific ideas, principles, and theories. x Construct an explanation that

includes qualitative or quantitative relationships between variables that predict(s) and/or describe(s) phenomena.

x Construct an explanation using models or representations.

x Construct a scientific explanation based on valid and reliable evidence obtained from sources (including the students’  own experiments) and the assumption that theories and laws that describe the natural world operate today as they did in the past and will continue to do so in the future.

x Apply scientific ideas, principles, and/or evidence to construct, revise and/or use an explanation for real-world phenomena, examples, or events.

x Apply scientific reasoning to show why the data or evidence is adequate for the explanation or conclusion.

Constructing explanations and designing solutions in 9–12 builds on K–8 experiences and progresses to explanations and designs that are supported by multiple and independent student-generated sources of evidence consistent with scientific ideas, principles, and theories. x Make a quantitative and/or qualitative

claim regarding the relationship between dependent and independent variables.

x Construct and revise an explanation based on valid and reliable evidence obtained from a variety of sources (including  students’  own  investigations, models, theories, simulations, peer review) and the assumption that theories and laws that describe the natural world operate today as they did in the past and will continue to do so in the future.

x Apply scientific ideas, principles, and/or evidence to provide an explanation of phenomena and solve design problems, taking into account possible unanticipated effects.

x Apply scientific reasoning, theory, and/or models to link evidence to the claims to assess the extent to which the reasoning and data support the explanation or conclusion.

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well they meet the criteria and constraints of the design solution.

x Apply scientific ideas or principles to design, construct, and/or test a design of an object, tool, process or system.

x Undertake a design project, engaging in the design cycle, to construct and/or implement a solution that meets specific design criteria and constraints.

x Optimize performance of a design by prioritizing criteria, making tradeoffs, testing, revising, and re-testing.

x Design, evaluate, and/or refine a solution to a complex real-world problem, based on scientific knowledge, student-generated sources of evidence, prioritized criteria, and tradeoff considerations.

C-E-R Framework and Assessment Probes (Contrasting Pre and Post Explanations)

The Mitten Probe Claim- Statement that expresses the answer to the probe question. The claim should be written in a complete sentence and stand alone (If someone read the claim, they would not need to see the probe to understand the claim). Example of a claim based on everyday experience: The temperature reading on a thermometer will increase after it is placed inside a mitten. Example of a scientifically based claim: The temperature reading on a thermometer does not increase after it is placed inside a mitten. --------------------------------------------------------------------------------------------------------------------

Evidence- Information that supports the claim. Scientific data come from observations in natural settings or controlled experiments, measurements, or valid scientific sources. Personal information comes from opinions, beliefs, and everyday experiences. There should be sufficient evidence (usually more than one piece of evidence if available). Evidence can be quantitative or qualitative. (Note: students may not yet have scientific evidence when using a probe for elicitation. After investigation and/or sense-making discussion, students should draw upon valid scientific evidence when revising their probe explanation). Example of evidence from every day experience: When I put mittens on, they warm up my hands. Example of scientific evidence: Temperature outside the mitten: 22 degrees C; Temperature after thermometer is inside mitten for 5 minutes: 22 degrees C; Temperature after 15 minutes inside mitten: 22 degrees C ---------------------------------------------------------------------------------------------------------------------

Reasoning- The justification that links the evidence to the claim. It explains why the evidence supports the claim. Scientific reasoning may include a scientific principle, concept, and/or appropriately used scientific terminology. Example of everyday reasoning based on a belief: The temperature increases because the mitten heats up the air inside of the mitten. Example of scientific reasoning: The temperature did not increase because a mitten is an insulator. It slows down the transfer of heat from our bodies when we wear mittens but it does not give off its own heat. --------------------------------------------------------------------------------------------------------------------- Based on the C-E-R Framework (McNeil and Krajcik, 2011) and adapted for use with the Uncovering Student Ideas in Science series.

Explanation- Combine the claim, evidence, and reasoning (C-E-R) Example of an explanation that draws upon a belief from everyday experience and indicates a misconception: The temperature reading on a thermometer goes up after it is placed inside a mitten. When I wear mittens, my hands are warmer. This is because the mitten gives off heat that warms my hands. Example of a scientific explanation: The temperature reading on a thermometer does not increase after it is placed inside a mitten. We took three temperature readings: outside the mitten-22 degrees C; inside the mitten for 5 minutes- 22 degrees C; and inside the mitten for 15 minutes- 22 degrees C. The temperature stayed the same outside of and inside the mitten. This is because a mitten is an insulator. It slows down the transfer of heat from our bodies when we wear mittens but it does not give off its own heat. ------------------------------------------------------------------------------------------------------------------ C-E-R with Younger Students: Note: With younger children, explanations may include only the claim and evidence if they do not have sufficient knowledge to use a scientific principal or concept or engage. They may use basic reasoning. Third grade is around the time students make transitions to include basic reasoning as a way to link their evidence to their claim. For example, a third grader pre-assessment probe response might be: I claim the temperature on a thermometer will go up after it is put inside a mitten. I think this because mittens warm up my hands when I wear them. The post-assessment response might be: I claim the temperature on a thermometer will stay the same after it is put in a mitten. My evidence is the temperature was 22 degrees C before we put it in the mitten. It was the same after we took it out of the mitten. Because the temperature stayed the same, my evidence supports my claim.

Based on the C-E-R Framework (McNeil and Krajcik, 2011) and adapted for use with the Uncovering Student Ideas in Science series.

Contrasting Pre and Post Students’ Explanations from the Formative Assessment Probes

Pre-Assessment Probe (Elicitation Prior

to Instruction) Post-Assessment Probe (After

Instruction) Claim Responds to the probe question

using one of the answer choices. Stated as a complete sentence. Stands alone- can understand what

the claim is without seeing the probe question.

Claim Responds to the probe question

using the best or scientifically correct answer choice.

Stated as a complete sentence. Stands alone- can understand what

the claim is without seeing the probe question.

Evidence At this stage students may not yet have scientific evidence to support their claim but they should draw upon some type of “evidence” whether it is from their experiences, prior knowledge or beliefs. Supports claim with some type of

“evidence”. Uses more than one piece of

“evidence” where appropriate.

Scientific Evidence Supports claim with appropriate

scientific evidence. Uses qualitative and quantitative

data (where appropriate). Cites valid sources of information

from text or other valid sources. Uses more than one piece of

scientific evidence where appropriate.

Reasoning (basic) Attempts to explain how the

evidence links to the claim. May attempt to use a scientific

principle or concept. Uses complete sentence(s).

Reasoning (more complex) Explains how the evidence links to

the claim. May use separate justifications for

each piece of evidence. Uses a scientific principle or

concept to show how the data support the claim.

Rebuttal Explains why other answers

(claims) are not supported. Uses scientific evidence to support

a rebuttal. Adapted from McNeill, K. and J. Krajcik (2012). Supporting Grade 5-8 Students in Constructing Explanations in Science. Boston, MA: Pearson, for use with the Uncovering Student Ideas in Science formative assessment probes.