“2008 Scripps National Spelling Bee” (8 p.m., ABC): Hunker down and break out the

“2008 Scripps National Spelling Bee” (8 p.m., ABC): Hunker down and break out the dictionary for the 2008 Scripps National Spelling Bee. The competition started earlier this week with nearly 300 youngsters, including an 8-year-old second-grader (the youngest contestant in the event’s history). Now comes the championship round hosted by Tom Bergeron.