Fifth-dumbest state in America: Mississippi The Magnolia State comes in virtually last place in two of the four factors we analyzed -- how many residents over 25 lack high-school educations and how many high-school students watch tons of TV. Research shows that 44.9% of Mississippi high schoolers spend three hours a day or more in front of the boob tube -- the worst ranking of any state measured. Similarly, the 19% of adult Mississippians who lack high-school degrees represent the second-highest rate nationally, besting only Texas and California (which tied for last place). The Magnolia State also ranks ninth-worst for young people attending college, with just 52.7% of 18- to 24-year-olds enrolled in high education. In fact, Mississippi's only bright spot among the factors we analyzed was its average SAT math scores. Students got a 544 mean score on the test in 2012 out of a possible 800 -- the 15th-best showing nationwide. Just 4% of Mississippi students generally take the SAT, though -- a low showing that can skew results. The College Board, which oversees the test, says low participation rates usually mean only the best students take the SAT, artificially inflating a state's average score. Fourth-dumbest state in America: Louisiana Louisiana's educational performance is no cause for a Mardi Gras parade. The Bayou State ties Kentucky for the third-highest proportion of adults without high-school degrees (18.1%), and has the sixth-lowest percentage of 18- to 24-year-olds enrolled in college (50.4%). And when it comes to television viewing, the 40.3% of Louisiana high schoolers who spend three hours or more a day watching TV trail only their Mississippi counterparts as the nation's highest ratio of budding couch potatoes. On the other hand, Louisiana's 536 average SAT math score does tie Montana for 17th place nationwide. But only 9% of Louisiana students typically take the test -- and as noted previously, low participation rates can skew a state's average upward.