Density Curriculum

Introduction

Overview

This curriculum module consists of fifteen lessons that can be used as a stand-alone unit or can be infused into a broader unit on density. The lessons are designed to address persistent difficulties that students have when learning about density. These difficulties stem from how students reason about the nature of cause and effect.

The module contains four sections. Each section introduces a challenge in thinking about causality that impacts students' ability to deeply understand density. The sections, and the multiple lessons within each section, are sequenced to build understanding. In each lesson, a background information section describes the difficulties that students typically have in learning about density, and shows how the various causal understandings, if not mastered, contribute to those difficulties. Each lesson includes subject matter goals and more general goals about the nature of causality. This module is designed for middle school, but can be adjusted for use with younger and older students.

Embedded within the lessons are special activities called RECAST activities. These activities are designed to REveal CAusal STructure, or help students RECAST their understandings so that they fit with the causal patterns that scientists use. RECAST activities typically have outcomes that don't fit with what students typically think, so they may serve as an impetus for students to restructure their understandings.

The curriculum is designed around "best practices" in science education. Lessons involve students in inquiry-based activities that ask them to observe and construct understandings. Lessons typically begin by asking students to examine their current beliefs and invite opportunities for students' ideas to evolve during the course of the unit. Student discussion is a central activity and teachers are encouraged to create an environment where students are comfortable sharing their ideas. Through discussion, students will realize that science involves revising ideas in a process of seeking the best explanation for the phenomenon in question.