1
At the close of the 18th century, the haze of fantasy and mysticism that tended to obscure the true nature of the Earth was being swept away. Careful studies by scientists showed that rocks had diverse origins. Some rock layers, containing clearly identifiable fossil remains of fish and other forms...
Grade Level   5 6 7 8 9 10 11 12
Classroom Activities Curricula and Instruction
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2
In ancient times, sailors found their way by observing stars and other celestial bodies — when they were visible through the clouds, that is. Thus, one of the most important improvements to ocean navigation was the invention of the compass. There is some disagreement about who should get...
Grade Level   6 7 8
Classroom Activities Curricula and Instruction
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