Siegfried "Zig" Engelmann (November 26, 1931 – February 15, 2019) was an American educationalist who co-developed the approach to instruction termed "Direct Instruction" (DI). Engelmann was Professor Emeritus of Education at the University of Oregon and Director of the National Institute for Direct Instruction. He wrote more than 100 curricula using DI principles and numerous other books and articles.
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