This resource is a set of three web-based labs for grades 7-9 relating volume, temperature, and pressure of a contained gas. Lab 1 investigates the effect of volume changes on the pressure of a confined gas at constant temperature. Lab 2 explores the effect of temperature changes on a confined gas held at constant volume. Lab 3 investigates the relationship between volume and temperature. Detailed lesson plans with objectives and assessment ideas are included. This item is part of a larger collection of interactive Java labs developed for use in middle school and high school. See Related items on this page for a link to the full collection.