In “Glee,” Blaine has an idea on how to win the nationals but it involves puppets, something the other glee members are not too sure of (Fox at 9 p.m.). (Mike Yarish/FOX)

Watch engineers and launch aficionados in Bridgeville, Del., compete in “Punkin Chunkin 2013” (Discovery at 8 p.m.), a comical competition where groups of varying skill try to come up with a contraption that launches pumpkins into the air. In the famed event, the team that hurls a pumpkin the farthest wins.

The pressure to win nationals is on, and Blaine has a plan for the competition that involves singing puppets on “Glee” (Fox at 9), but the other glee club members aren’t totally sold on his idea. Elsewhere, Kurt’s band is having difficulty settling on a venue for its first gig, and viewers finally get to find out the origins of Sue’s signature tracksuit.

The chief executive of Fatburger sees a different side of his business and goes undercover serving food at one of his many restaurants on “Undercover Boss” (TLC at 9).

“Modern Family” (ABC at 9) airs a repeat episode from earlier this season that has Jay and Gloria planning a surprise party for Manny’s 14th birthday. Haley shows interest in an older man, which sends her parents into a panic, and Cameron worries that Lily is closer to Mitchell.

“Lady Gaga & the Muppets’ Holiday Spectacular” (ABC at 9:30) has Lady Gaga and Kermit the Frog performing some tunes from her 2013 album, “Artpop,” in this over-the-top special. Elton John, Joseph Gordon-Levitt and RuPaul are also slated to duet with the songstress. The Muppet clan will be doing renditions of seasonal classics by the Swedish Chef, Beaker and Animal. Actress Kristen Bell also will make a special appearance.

A peek at the sixth season of “Doc Martin: Revealed” (WETA at 10) gives viewers a behind-the-scenes look into the production behind Large’s restaurant and the real pub that doubles as the Crab & Lobster.

On “Alaska: The Last Frontier” (Discovery at 10), the Kitchers celebrate a very different Thanksgiving from your typical turkey-and-potatoes affair.

Celebrity animal trainer “Jungle” Jack Hanna joins “The Late Show With David Letterman” (CBS at 11:35), along with “Big Bang Theory” actor Kunal Nayyar.

Pop star and TV judge Christina Aguilera visits “The Tonight Show With Jay Leno” (NBC at 11:35) with comedian Jay Mohr.

Actress Elizabeth Banks and TV host Larry King come to “Jimmy Kimmel Live” (ABC at 11:35), along with a musical performance from Daughtry.

— Rachel Lubitz