Sail the Circulatory System
- ToxRAP offers an interactive educational demonstration on hemoglobin and the carriage of oxygen throughout the body.
- http://www.toxrap.org/36_kids_game1intro.html

Habits of the Heart
- Explore the heart and lungs through online science activities.
- http://www.smm.org/heart/

Virtual Body
- Information on the heart, brain, skeleton, and digestive system. Includes some animations.
- http://www.ehc.com/vbody.asp

Thinkquest: Blood
- Information about blood diseases and blood types.
- http://library.thinkquest.org/04oct/01716/

How the Heart Works: The Heart House
- From the Children's Heart Institute, a diagram comparing a heart to a house.
- http://www.childrensheartinstitute.org/educate/heartwrk/hearthse.htm

Blood: The River of Life
- Thinkquest site provides detailed information with graphics and concise explanation about the workings of the human blood and the circulatory system. Includes safety tips to follow at home as well as interactive forums.
- http://library.thinkquest.org/C0115080

The Heart and Circulation
- A well illustrated interactive educational resource about the heart and heart disease. Includes a quiz.
- http://www.schoolscience.co.uk/content/4/biology/abpi/heart/

Circulatory System
- Multiple-choice quiz with crossword puzzle.
- http://www.vtaide.com/png/blood-mcq.htm

To Heal A Heart
- A PBS program about preventing heart disease. Includes frequently asked questions, an overview of heart disease, risk factors, pet scans, lesson plans, and a bibliography.
- http://www.pbs.org/healaheart/

NOVA Online: Electric Heart
- This is the story of a handful of brilliant, obsessed surgeons and researchers who pursued the target of a practical artificial heart for decades. Includes heart facts, an overview of a heart transplant, and artificial heart technology.
- http://www.pbs.org/wgbh/nova/eheart/

HeartPoint
- A multimedia site, showing animations of what different behaviors and lifestyles will do to one's circulatory system. Offers health tips and food recommendations.
- http://www.heartpoint.com/

The Heart: An Online Exploration
- From the Science Learning Network, visitors will learn about the heart, blood vessels, circulatory system development, cardiovascular health, and a history of heart medicine.
- http://sln2.fi.edu/biosci/heart.html