Scholastic
Scholastic: Dirtmeister's Science Lab: The Air Is There
An experiment to see how the temperature of an object affects how high it bounces. This site contains web links and notes for the teacher.
University Corporation for Atmospheric Research
Ucar: How High Does the Atmosphere Go?
This lesson shows the parts of the atmosphere and their size (thickness) relative to the size of the Earth. It includes background information, lesson outline, links to standards and assessments.
Science and Mathematics Initiative for Learning Enhancement (SMILE)
Smile: Does Air Really Exist?
Given a teacher demonstration and various learning stations, the students learn that air is a real substance which occupies space, exerts pressure, and has weight.