As more colleges are pushing professors to go digital and record their lectures as downloadable files for podcasts, critics question whether podcasting lectures will contribute to learning. Students, some professors say, might be tempted to skip class and the discussion that can flow after a lecture. Others worry that many educators are turning to podcasts simply because it is hip. Supporters say podcasts help students study better, allowing them to return to the part of an introductory lecture they didn't understand and hit repeat.