Education Dive – Shawna De La Rosa 
This newest study shows students whose teachers had the highest grading standards scored 16.9% of a standard deviation over those with low-expectation teachers. Tougher grading practices also translated into higher achievement in the subsequent Geometry and Algebra II courses. In Geometry, students whose teachers had high grading standards in Algebra I scored 7.3% of the standard deviation. In Algebra II, that group scored 8.6% of SD.
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