Science is always changing. Its very nature requires that scientists constantly revise theories to make sense of new observations. As they learn science, students are also constantly revising how they make sense of their observations, which requires comparisons with what they already know to process new information. A teacher can take advantage of…

The seasons are often modeled for students using two spherical objects, one representing the Sun and one representing the Earth. Solely using this model, however, neglects a critical aspect of learning--how students actually see the world. This lesson challenges students to explore seasonal variations as they create and analyze sunrise/sunset…

In this article, the authors describe a series of activities they have used with middle-level students. The first set of lessons explores density through the layering of liquids. In the second set, they use some of the same liquids to explore the density of solids. The third set investigates how temperature affects the density of…

When students enter the classroom, they often hold prior knowledge or conceptions about the natural world. These conceptions will influence how they come to understand what they are taught in school. Some of their existing knowledge provides good foundation for formal schooling, but other prior conceptions, however, are incompatible with currently…

The inertial balance is one device that can help students to quantify the quality of inertia--a body's resistance to a change in movement--in more generally understood terms of mass. In this hands-on activity, students use the inertial balance to develop a more quantitative idea of what mass means in an inertial sense. The activity also helps…

Student preconceptions are one of the greatest challenges facing science teachers. Students will often hold on to their explanation even after being told the correct explanation. They need to be challenged with experiences that they can not explain using their existing models of the world in order to see real change in their preconceived notions.…

Density is a derived quantity that can be confusing for middle school students. In this article, the author describes how he used a graphical depiction of mass and volume to guide his sixth-grade students in understanding and applying this concept. In the activity, students collected various materials, then discussed and tested whether each of the…

Designing assessments to effectively probe students' understanding of science concepts is a challenge that requires having an overall assessment strategy and well-designed assessment instruments. For assessments to be most effective they need to be continuously woven throughout teaching and learning, and the results need to be used to inform…

Describes the use of concept maps and Vee maps in science instruction. (PR)

Presents a lesson designed to help students understand the concept of density. Provides students with a concrete experience to help them understand an abstract concept thereby providing another strategy for learning the concept. (JRH)

Describes the use of Vee maps in helping students understand scientific investigations. (PR)

Proposes having students perform skits in which they play the roles of the science concepts they are trying to understand. Provides the dialog for a skit in which hot and cold gas molecules are interviewed on a talk show to study how these properties affect wind, rain, and other weather phenomena. (MDH)

Presents an activity in which models help students visualize both the DNA process and transcription. After constructing DNA, RNA messenger, and RNA transfer molecules; students model cells, protein synthesis, codons, and RNA movement. (MDH)

Proposes having students write about what they learned from science films as a method of evaluating the effectiveness of the film. Supplies examples of students' writing on films and techniques for exploiting the results. (MDH)