These lessons introduce a scientific understanding of density, a concept found on the HSE math and science tests.

Each section includes a full lesson plan, activity sheets, answers to activity sheets, background material for teachers in the form of readings and introductory videos, student readings and videos. Some of the videos introduce the material to teachers so they understand the science and the purpose of the lesson. Other videos help students understand the material. Demonstrations are mostly done with common materials you can buy at a supermarket. Highly recommended.

The full 740-page Middle School Chemistry curriculum is available for download.