From the Dept. of "It's All Relative," allAfrica.com is reporting that student achievement in Nigeria is plummeting because of exploding class sizes. High school teachers routinely have to deal with 150 to 200 students in a class and never below 100. Class sizes have been swelling up for the past two decades when the government instituted free public education but didn't quite figure out how to pay for it. Actually, that's not an altogether unfamiliar concept in this country either.