However, by this time the tide was turning and many leading educators were questioning the effectiveness of mixed ability teaching.

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"Controlled assessments are cumbersome and time-consuming and restrict the ability of schools like MGS to provide inspirational teaching for the most able pupils, " he said.

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In 1920, HBS innovated the case method of research and teaching where students literally sink or swim entirely on the basis of their ability to persuade peers that their analysis and recommended course of action is the right one for the company in question.

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But his current position provides prestige and the ability to influence, the satisfactions of teaching and discourse with colleagues.

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The nation's ability to direct most of its college-trained women into the single career of teaching was the foundation upon which the national public school system was built and a major reason American tax rates were kept low.

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