Physics4kids
Rader's Physics4 kids.com: Thermodynamics & Heat: First Law of Thermodynamics
Explains how the first law of thermodynamics affects four types of thermodynamic systems.
Museum of Science
The Atoms Family
Let this classic family of monsters guide you as you learn about energy. Interactive exercises, experiments, and demonstrations help to build knowledge and raise questions.
University of Sydney (Australia)
Equations for Thermodynamics
An exhaustive list of equations and formulas which are commonly used in thermal physics (including equations for triple point). Equations are organized according to category. Meaning of the symbols is clearly stated.