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 4 Sample Student Responses represent a range of score points.

Sample Student Response #1

image of student response

Score for Sample Student Response #1: Rubric Score 1

Annotation: This response contains evidence of some understanding of the question. The student states why the conclusion is misleading (only used 100 households) and briefly describes how to redesign the experiment (given the product samples to more households). The supporting details are minimally effective. More supporting details are needed for a higher score. Compare to Anchor Paper #1.
Sample Student Response #2

image of student response

Score for Sample Student Response #2: Rubric Score 2

Annotation: This response contains evidence of a basic understanding of the question. The student states two reasons why the conclusion is misleading (only a small sample of people; don't know what kind of mildew is removes) and provides two ways to redesign the experiment (increase the number of times you did the experiment…do it 200 times; you could do it…on specific, lab grown mildews.) The supporting details are adequate. Compare to Anchor Paper #4.
Sample Student Response #3

image of student response

Score for Sample Student Response #3: Rubric Score 4

Annotation: This response contains evidence of a full and complete understanding of the question. The student explains how various interpretations of "effectiveness" could be the basis of a misleading conclusion (one person might have considered…effective if it removed all…while another might have considered…effective if it removed some) and explains how too many variables and a lack of control results in unreliable results (type of mildew, length of time, amount used, conditions of the area, no prior experiment, and no control group). Suggestions for redesigning the experiment are given and discussed (asked each household to record the conditions under which the product was used; set up a control group; set up the experiment in a controlled environment; used a larger sample size). The supporting details throughout this response are pertinent and complete, and reflect an integration of ideas. Scientific terminology enhances this response (control group; variables). Compare to Anchor Paper #5.
Sample Student Response #4

image of student response

Score for Sample Student Response #4: Rubric Score 3

Annotation: This response contains evidence of a good understanding of the question. The student discusses how a misleading conclusion could result from not controlling variables (how the product was used; the degree in which the mildew was "removed"; the way in which the mildew was used varied from house to house; mildew in the bathroom as opposed to that in the kitchen.) Remedies for these problems (specified dosage and usage) are then given. More integration of information is needed for a higher score. The supporting details are generally complete. Compare to Anchor Paper #5.

Additional Resources

Anchor Papers used in scoring

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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