TONIGHT'S MUST-SEE

"American Idol," 7 p.m., and "Are You Smarter Than a 5th Grader?" 8:30; both Fox. "Idol" again stretches to three nights. Tonight, it has the 10 men, trying to recover from their weak showings last week; the 10 women, who have been great, are Wednesday. On Thursday, the field will be trimmed to eight apiece. That will continue for one more week until the show has its 12 finalists. This time, at least, it will help nudge something new. Produced by Mark Burnett ("Survivor"), the new show asks grown-ups questions from a fifth-grade textbook. (What are the five Great Lakes? What state is Mount Rushmore in?) Jeff Foxworthy hosts, and this could be fun.

"To Iraq and Back: Bob Woodruff Reports," 9 p.m., ABC. Bob Woodruff had barely begun his duties as co-anchor of the ABC newscast when he was seriously injured in an Iraq bombing. Now, 13 months later, he reports on his recovery and on the treatment of wounded U.S. soldiers.

OF NOTE

"NCIS," 7 p.m., CBS. Dismembered bodies have been found inside a military mausoleum. Now the team hunts for a serial killer.

"The Unit," 8 p.m., CBS. The team ends up battling tribal warriors in a border battle in Pakistan.

"Law & Order: Criminal Intent," 8 p.m., NBC. For the second straight Tuesday, a man who is slowly dying of poisoning wants to make sure his own murder is solved. Last week, that was on "NCIS." Now Detective Logan (Chris Noth) is on the case.

"Frontline: News War, What's Happening to the News," 9 p.m., PBS. In the first two parts of this series, Lowell Bergman viewed the tug between government and the news media. Now he looks at a key problem on one side — financial pressure has crippled news efforts. Suddenly, Ted Koppel argues, news people are told to match entertainment shows in ratings. "That may prove to be one of the greatest tragedies in the history of American journalism."

"Law & Order: Special Victims Unit," 9 p.m., NBC. A difficult rape case takes Benson to New Jersey, where she collides with a tough cop (Kim Delaney). Back home, that case and others send her to see a psychiatrist played by Mary Stuart Masterson.