After school officials discovered many students may have shared answers or plagiarized on a final exam, an investigation has started.  Harvard officials cannot release the name of the class, the students' names or the exact number being investigated. Roughly half of the undergraduate class had possible cheating in the take-home exams.  "These allegations, if proven, represent totally unacceptable behavior that betrays the trust upon which intellectual inquiry at Harvard depends," President Drew Faust said.