S4, E5: Professor Krick gives Charles his first student teaching assignment, creating a history test that two of the college's star football players can pass. If they flunk the test, they get kicked off the team, and Charles gets kicked out of college. But rather than giving them a simpler test, Charles is determined to tutor the athletes until they can pass the same test the rest of the class will be taking. In the meantime, Lillian has bought an old diner and turned it into a 50's eatery called "The Yesterday Cafe." Although it looks very authentic, right down to the menus made from actual 50's newspapers, no one shows up for the grand opening, leaving everyone with doubts about the restaurant's succeeding.