8 h 37 m, 20 ene 1880 año - Grade level system
Descripción:
The National Education Act and the United States Office of Education adopted a chronological system of grade levels by children's age. This made it obvious to spot where children were standing out from.Source: Special Education in a Contemporary Society. 6th Ed.
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8 h 37 m, 20 ene 1880 año
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~ 144 years ago
