Pendulums

Ms. D. wants to focus on inquiry. She wants students to develop an understanding of variables in inquiry and how and why to change one variable at a time. This inquiry process skill is imparted in the context of physical science subject matter. The activity is purposeful, planned, and requires teacher guidance. Ms. D. does not tell students that the number of swings depends on the length of the pendulum, but creates an activity that awakens students' interest and encourages them to ask questions and seek answers. Ms. D. encourages students to look for applications of the science knowledge beyond the classroom. Students keep records of the science activities, and Ms. D. helps them understand that there are different ways to keep records of events. The activity requires mathematical knowledge and skills‥ The assessment, constructing a pendulum that swings at six swings per second, is embedded in the activity.

[This example highlights some elements of Teaching Standards B, C, and D; Assessment Standard B; 5-8 Content Standards A and B; and Program Standard C.]

The students in Ms. D.'s fifth grade class are studying motion, direction, and speed. One experiment in this study is designed to enable the students to understand how and why to change one variable at a time. Ms. D. has the students form groups of four; each student has an assigned role. One student—the materials manager—goes to the supply table to pick up a length of string, scissors, tape, and washers of various sizes and weights. Each group is directed to use these materials to 1) construct a pendulum, 2) hang the pendulum so that it swings freely from a pencil taped to the surface of the desk, and 3) count the number of swings of the pendulum in 15 seconds.

The notetaker in each group records the result in a class chart. Ms. D. asks the students to examine the class data. Because the number of swings recorded by each group is different, a lively discussion begins about why this happened. The students decide to repeat the experiment to make sure that they have measured the time and counted the swings correctly. When the second set of



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