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Soiled Again
Administration Procedures
Contributed by: Connecticut Academic Performance Test (CAPT)


The CAPT Science Framework was developed by an advisory committee of Connecticut educators and is based on current research and theory about science instruction and assessment. The CAPT Science Framework is based on the idea that science is not only a body of knowledge, but also a way of thinking about the world around us and a concern how that knowledge is used. The framework thus addresses three major questions: What do students know in science? (Conceptual Understanding), What do students do with their scientific knowledge? (Application), and How do students know in science? (Experimentation). The content is drawn from three major areas (Life Science, Physical Science, and Earth/Space Science). The CAPT Science Framework was developed using the Connecticut Guide to Curriculum Development in science, as well as various national efforts in science education including Project 2061's Science for All Americans, the National Science Teachers Association's Scope, Sequence and Coordination's Content Core and the emerging National Science Education Standards. It should be noted that the science component of the CAPT is not a test of high school science content, but rather a cumulative assessment covering science content and skills that students should have acquired in grades K-10.

Assessing Experimentation

Science is not a matter of belief; rather, it is a matter of conclusive evidence that can be subjected to the tests of observation and objective reasoning. Experimentation and the ability to apply scientific reasoning to solve problems is a major focus of the science assessment.

To assess experimentation, students participate in a hands-on laboratory activity several weeks prior to the written test. This performance task asks students to design and carry out their own experiment to solve a problem and write about their results in an authentic format. Students are not scored on their actual performance on this task at the state level. Rather, teachers are encouraged to score their own students' work and provide students with feedback about their performance. On the written test, students are given follow-up questions which relate directly to the hands-on task. These questions are scored at the state level and become part of the student's score on the science portion of the CAPT.

CAPT Science Processes

  1. Conceptual Understanding and Application
    • Description - use of scientific knowledge to provide accurate names for natural phenomena and for purposes of classification
    • Explanation - use of scientific knowledge to explain natural phenomena
    • Prediction - use of scientific knowledge to generate predictions about future events
    • Application - use of scientific reasoning and knowledge to solve daily life problems and technological problems, recognizing its potential and limitations
    • Communication - use of scientific words, graphs, charts and equations to explain scientific phenomena

  2. Experimentation
    • Define the problem
    • Formulate a hypothesis
    • Test the hypothesis: design and conduct appropriate experiments
    • Make, record, and interpret observations
    • Draw conclusions and discuss their validity

CAPT Science Content Areas

  1. Life Science
    • Characteristics of living things
    • Cells, genetics, and evolution
    • Ecosystems
    • Human biology
    • Issues in bioethics

  2. Physical Science
    • Structure of matter
    • Reactions and interactions
    • Force and motion
    • Energy sources and transformation
    • Heat and temperature
    • Magnetism and electricity
    • Sound and light

  3. Earth/Space Science
    • Astronomy
    • Geology and natural resources
    • Oceanography
    • Meteorology
    • Earth history and dynamics

National Science Education Standards:

12 A SI 1: Science as Inquiry: Grades 9-12

1.2 Plan and conduct an investigation. In the earliest years, investigations are largely based on systematic observations. As students develop, they may design and conduct simple experiments to answer questions. The idea of a fair test is possible for many students to consider by fourth grade.

1.4 Use data to construct a reasonable explanation. This aspect of the standard emphasizes the studentsí thinking as they use data to formulate explanations. Even at the earliest grade levels, students should learn what constitutes evidence and judge the merits or strength of the data and information that will be used to make explanations. After students propose an explanation, they will appeal to the knowledge and evidence they obtained to support their explanations. Students should check their explanations against scientific knowledge, experiences, and observations of others.

1.5 Communicate investigations and explanations. Students should begin developing the abilities to communicate, critique, and analyze their work and the work of other students. This communication might be spoken or drawn as well as written.

4 D ESS 1: Properties of earth materials: Grades K-4

1.1 Earth materials are solid rocks and soils, water, and the gases of the atmosphere. The varied materials have different physical and chemical properties, which make them useful in different ways, for example, as building materials, as sources of fuel, or for growing the plants we use as food. Earth materials provide many of the resources that humans use.

(Use the "hot" link on the PALS home page to check the full text of related National Science Education Standards, if desired.)

National Council of Teachers of Mathematics:

DAP1: Formulate questions that can be addressed with data and collect, organize, and display relevant data to answer them:
Grades 9-12 j. understand the differences among various kinds of studies and which types of inferences can legitimately be drawn from each
Grades 9-12 k. know the characteristics of well-designed studies, including the role of randomization in surveys and experiments
Grades 9-12 l. understand the meaning of measurement data and categorical data, of univariate and bivariate data, and of the term variable
Grades 9-12 m. understand histograms, parallel box plots, and scatter plots and use them to display data

DAP3: Develop and evaluate inferences and predictions that are based on data:
Grades 9-12 h. evaluate published reports that are based on data by examining the design of the study, the appropriateness of the data analysis, and the validity of conclusions

PS3: Apply and adapt a variety of appropriate strategies to solve problems:
Grades 9-12

RP3: Develop and evaluate mathematical arguments and proofs:
Grades 9-12

CNX3: Recognize and apply mathematics in contexts outside of mathematics:
Grades 9-12

CAPT Science Performance Task: Soiled Again
Grade 10

Many lakes in the Northeastern United States appear to be suffering harmful effects from acid rain. Although they often look crystal clear, these lakes have significant decreases in their number of fish and other life forms.

Yet other lakes in the same region seem healthy. The reason may have to do with the rocks and soil that surround the lakes. Some rain falls directly into rivers and lakes, but much of it hits the ground first and then flows or seeps into the bodies of water. When acid rain flows through soil and gravel that have a higher pH than the rain, the pH of the rain may change. The rate at which the rain percolates or seeps through the soil and gravel is another important factor that affects the neutralization of the acid. If it seeps through too quickly, there may not be time for a noticeable change in pH to occur.

Student's Task:
The students will design and conduct an experiment to determine which earth material (sand, potting soil or limestone) or combination of earth materials will best reduce the acidity of "acid rain." During this activity they will work with a lab partner (or possibly two partners). The students must keep their own individual lab notes because after they finish, they will work independently to write a report "to the planning commission" that is trying to decide which earth material should be used around a local lake in order to reduce the effects of acid rain.

The materials listed below should be provided for each lab group. It may not be necessary for the students to use all of the equipment that is provided. You may use additional materials or equipment if they are available.

Sand (1/2 cupful)
Potting soil (1/2 cupful)
Crushed limestone (1/2 cupful)
Vinegar (200 mL)
Tap water
pH test strips (10) and pH color chart
Access to a balance
Access to a clock or a watch with a second hand
Access to a calculator
Paper towels for clean-up
Safety equipment (including goggles and aprons)
Plastic spoon
Paper cups (8)
Square bandages (4)
Wooden sticks (6)
Graduated cylinder
Large beaker

Soiled Again

Item 1
This item is intended to assess students' ability to define a scientific problem in their own words. In this experiment, there are two related problems that are being investigated; comparison of the rate of percolation of three different earth materials, and comparison of the neutralizing ability of the three earth materials. Response should clearly state the independent and dependent variables to be investigated.
CAPT Framework
Experimentation: Define the Problem.

Item 2
This item is intended to assess students' understanding of the need to conduct controlled experiments when investigating the effect of one variable on another. The variables that need to be controlled in this experiment include the initial amount of acid rain solution poured through the materials, the initial pH of the acid rain solution, the amount of earth material, the size of the hole in the cup, and the amount of gauze used.
CAPT Framework
Experimentation: Design and conduct appropriate experiments.

Item 3
This item is intended to assess students' understanding of what constitutes a complete and appropriate experimental design. In this case, students do not have all of the information that they need to replicate the experiment. Additional information that students would need to know includes how much earth material was used and how much acid rain solution was used.
CAPT Framework
Experimentation: Design and conduct appropriate experiments.

Item 4
This item assess students' ability to draw conclusions based upon data and to consider the validity of those conclusions. For this experiment, the group's conclusion should not be considered valid because while both the sand and potting soil changed the pH of the acid rain solution from 3.0 to 3.5, the sand allowed more solution to pass through in the given time. It is also unclear whether or not the group controlled important variables such as those described in Item 2. This group's experiment also included only one trial which casts doubt on the validity of the results.
CAPT Framework
Experimentation: Make, record and interpret observations/Draw conclusions and discuss their validity.


  • Be careful.
  • Teachers and students should always exercise appropriate safety precautions and utilize appropriate laboratory safety procedures and equipment when working on science performance tasks.


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