The answer, says James D. Yager, senior associate dean for academic affairs at the Bloomberg School of Public Health at Johns Hopkins University, lies in why students pay to attend university in the first place. What OpenCourseWare offers, he notes, is not the full university experience: “We don’t offer the course for free, we offer the content for free,” Mr. Yager said by telephone in February. “Students take courses because they want interaction with faculty, they want interaction with one another. Those things are not available on O.C.W.