The ranks of the most expensive colleges have grown again: 100 institutions are charging $50,000 or more for tuition, fees, room, and board in 2010-11, according to a Chronicle analysis of data released last week by the College Board. That?s well above the 58 universities and colleges that charged that much in 2009-10, and a major jump from the year before, when only five colleges were priced over $50,000.