School Improvement in Maryland
Public Release Item Scoring Information Return

Goal 1 Skills And Processes

Expectation 1.1 The student will explain why curiosity, honesty, openness, and skepticism are highly regarded in science.

Indicator 1.1.3 The student will critique arguments that are based on faulty, misleading data or on the incomplete use of numbers.

Brief Constructed Response (BCR) Item - Released in 2003

Researchers tested a new product designed to remove mildew from household surfaces. They gave free samples of the product to 100 different households. They collected these data: 70 households reported that the product was effective in removing mildew; 30 households reported that the product was not effective in removing mildew. From these data, the researchers concluded that the product was 70% effective in removing mildew from household surfaces.

  • Why is this a misleading conclusion?
     
  • In your response, discuss how this experiment could be designed to give more reliable results.
Type your answer in the answer box below.

The following 7 Anchor Papers represent a range of score points and are used in conjunction with the rubric to assess student responses.

Anchor Paper #1

image of student response

Score for Anchor Paper #1: Rubric Score 1

Annotation: This response contains evidence of some understanding of the question. The student believes that the product really is 70% effective. Minimal supporting details are used to discuss how this experiment could be redesigned (every household {should have} the same surface to sample).


Anchor Paper #2

image of student response

Score for Anchor Paper #2: Rubric Score 1

Annotation: This response contains evidence of some understanding of the question. Although the student does not explain why the conclusion is misleading, the response discusses how to redesign the experiment to give more reliable results (test another 200 households; make sure the person is applying the cleaner properly; ask the people to apply the cleaner more than once). The supporting details are minimally effective.


Anchor Paper #3

image of student response

Score for Anchor Paper #3: Rubric Score 2

Annotation: This response contains evidence of a basic understanding of the question. The student refers to the need for controlling variables (30% of the time it didn't work maybe the people who were using it had a lot of more mildew's than the 70% of the people who said it was effective) and provides a discussion of how to redesign the experiment (didn't do the experiments in enough houses. The greater the number of samples they would have given out the better the outcome.) Supporting details throughout this response are adequate.


Anchor Paper #4

image of student response

Score for Anchor Paper #4: Rubric Score 2

Annotation: This response contains evidence of a basic understanding of the question. The student uses adequate supporting details to discuss the need for controlling variables (conditions might have been different; mildew buildup could have been greater; the product might have been misused) and to discuss how this experiment could be redesigned (testing in a laboratory with exactly the same conditions). More elaboration and/or use of accurate scientific terminology is needed for a higher score.


Anchor Paper #5

image of student response

Score for Anchor Paper #5: Rubric Score 3

Annotation: This response contains evidence of a good understanding of the question. The student explains why the conclusion is misleading (it is reflecting different people's opinions of whether or not the product was effective; one family that reported the product was ineffective and one that reported it was effective could have in reality had the same amount/percentage of mildew killed). The experimental redesign contains specific details (grow mildew in 100 petri dishes, observe, calculate the percentage of mildew, and average the percentages) and is designed according to the scientific method. The supporting details are generally complete.


Anchor Paper #6

image of student response

Score for Anchor Paper #6: Rubric Score 3

Annotation: This response contains evidence of a good understanding of the question. An explanation of why the conclusion is misleading shows some synthesis of information and a need to control variables (conditions in which the product was being tested was not constant throughout the different households; there could have been more mildew build up in one household than in another; The people testing the mildew remover could have also applied the product differently). The student explains why the interpretation of the data is misleading (couldn't say that this product was 70% effective, because in some homes, it was 0% effective). The redesign (researchers should set standards for…usage, mildew-buildup, pH, temperature) is a list of information which would need further elaboration for a higher score.


Anchor Paper #7

image of student response

Score for Anchor Paper #7: Rubric Score 4

Annotation: This response contains evidence of a full and complete understanding of the question. The student synthesizes ideas into an explanation of why the data is misleading (the formula was either 100% effective or 0% effective…the actual conclusion should have been is that it works 70% of the time because the households reported that it either was 100% effective or 0% effective) and how to redesign the experiment (the product was tested in only 100 houses; could be tested on 5,000 homes; houses tested might have had mildew growing at different rates on different surfaces; there was no control group). Each of the conclusions drawn is supported by pertinent and complete supporting details which results in a complete integration of information. Scientific terminology enhances this response (control group).


Brief Constructed Response (BCR) Rubric
Print: Scoring Rubric (pdf)
Score 4

There is evidence in this response that the student has a full and complete understanding of the question or problem.

  • Pertinent and complete supporting details demonstrate an integration of ideas.
  • The use of accurate scientific terminology enhances the response.
  • An effective application of the concept to a practical problem or real-world situation reveals an insight into scientific principles.*
  • The response reflects a complete synthesis of information.
Score 3

There is evidence in this response that the student has a good understanding of the question or problem.

  • The supporting details are generally complete.
  • The use of accurate scientific terminology strengthens the response.
  • The concept has been applied to a practical problem or real-world situation.*
  • The response reflects some synthesis of information.
Score 2

There is evidence in this response that the student has a basic understanding of the question or problem.

  • The supporting details are adequate.
  • The use of accurate scientific terminology may be present in the response.
  • The application of the concept to a practical problem or real-world situation is inadequate.*
  • The response provides little or no synthesis of information.
Score 1

There is evidence in this response that the student has some understanding of the question or problem.

  • The supporting details are only minimally effective.
  • The use of accurate scientific terminology is not present in the response.
  • The application, if attempted, is irrelevant.*
  • The response addresses the question.
Score 0

There is evidence that the student has no understanding of the question or problem.

  • The response is completely incorrect or irrelevant or there is no response.

* On the High School Assessment, the application of a concept to a practical problem or real-world situation will be scored when it is required in the response and requested in the item stem.

Updated 2002
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