Strong students benefit from online classes, but weak students do not, concludes Brookings’ Susan Dynarski. The convenience of online learning appeals to adults with full-time jobs and often with children to raise. But these high-risk students do substantially worse online than similar students fare in face-to-face courses, concludes a Stanford study of students at a large, for-profit college. In “blended” courses, which combine face-to-face instruction with online learning,