Formative Assessment in Modeling Instruction

Assessment 2010
Formative Assessment in Modeling Instruction
Synopsis of Modeling Instruction:
In the Modeling Instruction Program, high school physics and chemistry teachers are trained
to be leaders in science teaching reform and technology infusion in their schools and school
districts. In a series of intensive workshops over two years, they are equipped with a robust
teaching methodology for developing student abilities to make sense of physical experience,
understand scientific claims, articulate coherent opinions of their own and defend them with
cogent arguments, evaluate evidence in support of justified belief.
More specifically, the teachers learn: (a) to organize course content around scientific models
as coherent units of structured knowledge; (b) to engage students collaboratively in making
and using models to describe, to explain, to predict, to design and control physical and
chemical phenomena; (c) to involve students in using computers as scientific tools for
collecting, organizing, analyzing, visualizing, and modeling real data; (d) to continuously
improve and update instruction with new software, instructional materials, and insights from
educational research. To sum up, the modeling workshops provide a detailed implementation
of the National Science Education Standards proposed by the National Research Council.
Almost all teachers who have completed the modeling workshop series have embraced the
new teaching methodology. Their subsequent teaching effectiveness has been evaluated with
a test of basic physics understanding on which there is public data for more than 10,000 high
school and college students. Students of teachers who have implemented the method most
fully achieved a high performance gain, surpassing that of students under traditional physics
instruction approaching two standard deviations.
Modeling Instruction is aligned with the assessment standards of the National Science
Education Standards. The summary gives the flavor: “more emphasis on assessing what is
most highly valued, assessing rich, well-structured knowledge, assessing scientific
understanding and reasoning, assessing to learn what students do understand, assessing
achievement and opportunity to learn, students engaged in ongoing assessment of their work
and that of others...” In the modeling method, embedded and authentic assessment are used.
Clearly, one role of assessment is to ascertain student mastery of the skills and understanding
of the concepts in the unit. An equally important role is the feedback it provides the
instructor, about the design of the activities and his or her implementation. The Modeling
Method stresses formative assessment as well as summative. Formative assessment has four
major components: practice worksheets, lab write-ups, lab practicums and whiteboarding.
Formative assessment includes developing a sound conceptual understanding using graphical
and diagrammatic representations before moving on to quantitative problem solving. To be
consistent with this end, assessment instruments provided in the instructional materials test
students’ ability to interpret graphs and draw conclusions, as well as to solve quantitative
Assessment 2010
problems using models developed on the basis of experiments done in class. As a simple
example, here is a header for a series of questions from Unit V, Test v1.
Below is the velocity vs. time graph for a train. Use the graph to answer questions
7 –10.
Students are asked to sketch the matching acceleration vs time graph. Then they are asked to
determine when (if ever) the net force acting on the train is zero, and during which interval
the force is the greatest. They must provide rationale for their answers.
In addition to lab write-ups, in which students report their findings using a format outlined in
the introductory section of the curriculum materials, the workshop manual provides
suggestions for use of the lab practicum as a means to check student understanding. In the
practicum, an application problem (a one-period-project) is posed to the entire class. The
class has a fixed time to figure out what model is appropriate to describe the situation, decide
what measurements to make, collect and analyze data, then prepare a solution. This is the
culminating activity in the unit that helps students review key principles for the unit test.
Whiteboarding is the fourth major component of assessment. What's different here is that it
serves purposes other than determining students' grades. First, it gives students a chance to
reinforce their understanding of concepts; students don't really know what they think until
they've heard themselves express the idea. Second, students are highly motivated to
understand the question they are assigned to present. No one enjoys getting up before a
group of peers with nothing to say. During preparation, the instructor has the opportunity to
help the students if no one in the group knows how to do the problem. Third, the activity is
diagnostic for it allows the instructor to determine how well the students have mastered the
concept. Students must account for everything they do in solving a problem, explaining why
they had done it that way, and ultimately appealing to models developed on the basis of
experiments that had been done in class. Instructors trained in the Modeling Method do not
take correct statements for granted. They always press for explicit articulation of students’
thinking. When instructors hear fuzzy or incoherent explanations, they have the opportunity
to help students deal with their incomplete conceptions before moving on to the next task.
The two most frequently asked questions are, “Why do you say that?” and “How do you
know that?” Presentations can be made sequentially (when groups present their solutions to
different problems) or simultaneously (when groups display and compare the results of their
experiments. In either approach, the instructor spends more time listening and guiding by
questioning than telling students what to think.