Homework Heaven is a huge online academic research directory, with over 12,000 hand picked links and 70 special school subject search engines. It's designed exclusively for students from K-12 through College level. The links provide access to specific information and research sources covering hundreds of school subjects.
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The heart history articles include a chronology of milestones in cardiology, from William Harvey's first description of blood circulation, in 1628, to Willem DeVries' first implant of a permanent artificial heart, in 1982. Highlights are the many colorful visuals, a movie illustrating blood circulation and, as you explore the site, a steady sound of a beating heart is in the background. A fifth main section presents 47 more chronologies of related subjects. The excellent and detailed Backyard Wildlife Habitat Planning Guide presented here will be appreciated by critters from every state, and provides fine lessons in wildlife conservation that begins at home or schoolyard. Food, water, plant cover, places to raise young, and other important matters are explained.