Claudia goes into labor at Lily’s graduation on the series finale of “Grounded for Life” (7:30 p.m., WB). Originally broadcast on Fox, this comedy debuted in January 2001. Its rough sensibilities seemed more appropriate to that network. “Grounded” was an odd fit for the WB, a network aimed almost exclusively at teenage girls.

The latest buzzword among TV programmers is “aspirational.” Shows are supposed to reflect the hopes and dreams of their audiences. Or rather, advertisers want their products to be associated with the hopes and dreams of their audiences. Apparently, tens of millions “aspire” to be a “Desperate Housewife” or to be a corpse on a “CSI” slab.

But rather than provide fantasies, “Grounded” reflects every teenage girl’s worst nightmare. Claudia (Megyn Price) finds herself pregnant in high school and marries her boyfriend, Sean (Donal Logue). Flash forward 15 years or so and Claudia and Sean are still trying to act like teenagers even while raising two of their own. But “Gilmore Girls” this is not. There are no millionaire parents to bail them out of car payments, no Yale-bound children or witty patter. Sean works at a bar when not engaged in Ralph Kramden-esque schemes with his brother Eddie (Kevin Corrigan).

In the end, “Grounded” failed not because it was an odd fit between “What I Like About You” and “Reba,” but because, like too many shows, it treated its characters with predictable contempt and condescension. “Grounded” followed the unwritten television rule dictating that blue-collar men must be loud, vulgar, slightly overweight, sex-obsessed and dim. And their much better-looking wives must bear with them with bemused resignation. Can you wonder why viewers, particularly young female viewers, don’t find this something to “aspire” to?

• “20/20” (9 p.m., ABC) correspondent John Stossel turns his attention to what he considers popular myths and assumptions. When people say, “The price of gas is higher than ever,” Stossel twitches his moustache and offers a “Gimme a Break” scowl.

Given the increases in the cost of living over the decades, you don’t have to be an economics wizard to determine that gas prices are not at their highest levels right now. Taking inflation into account, the $1.56 per gallon petrol I pumped into my 1962 Chevy II Nova during the summer of 1976 was much more expensive than the $1.81 per gallon gas I purchased yesterday. I’m sure Stossel will make this point with his usual air of exasperated condescension.

But will Stossel stop to consider the rise in the cost of gas relative to the rise in income? After all, people don’t fret about the price of gas, milk or rent relative to some nostalgic benchmark. They complain when prices go up faster than the numbers on their paychecks. Will Stossel take this into account? We’ll just have to tune in to find out.

Stossel also vents his displeasure over such irksome topics as pork-barrel spending, littering and surcharges on your phone bills. Stop the presses: littering is bad!

Tonight’s other highlights

• Hilary Duff guest stars on “Joan of Arcadia” (7 p.m., CBS).
• On back-to-back episodes of “Bernie Mac” (Fox), Jordan grows a poker face (7 p.m.), Bernie and his rival, Chris Rock (as himself), share a stage (7:30 p.m.).
• Death rides the roller coaster on “CSI” (8 p.m., CBS).
• With Don (Rob Morrow) in pursuit of bank robbers, Charlie (David Krumholtz) tries to calculate their next step on “Numb3rs” (9 p.m., CBS), now in its regular time slot.
• A rare brain disorder spreads at an arctic outpost on “Medical Investigation” (9 p.m., NBC).

Series notes

Rory refuses to finger the bully who attacked him on “8 Simple Rules” (7 p.m., ABC) … Diplomacy fails on “Star Trek: Enterprise” (7 p.m., UPN) … Vince sees an opening on “What I Like About You” (7 p.m., WB).

Cafeteria duty on “Complete Savages” (7:30 p.m., ABC) … Jonny tutors a young female boxer in and out of the ring on “Jonny Zero” (8 p.m., Fox) … A catered affair on “Hope & Faith” (8 p.m., ABC) … Missy Elliott hosts “The Road to Stardom” (8 p.m., UPN) … Van hires a maid on “Reba” (8 p.m., WB) … Charlie moves in with Claude on “Less Than Perfect” (8:30 p.m., ABC) … Friends in need on “Blue Collar TV” (8:30 p.m., WB).

Late night

Samuel L. Jackson, Amy Poehler and B.B. King appear on “Late Show with David Letterman” (10:35 p.m., CBS) … Jay Leno hosts Kiefer Sutherland, Rachel Ray and Tift Merritt on “The Tonight Show” (10:35 p.m., NBC) … Jay Mohr, Ja Rule and Phil Vassar appear on “Jimmy Kimmel Live” (11:05 p.m., ABC).

Halle Berry, Christopher Meloni and Erinn Smart chat on “Late Night with Conan O’Brien” (11:35 p.m., NBC) … Craig Ferguson hosts Vanessa Williams, Scott Wolf and Razorlight on “The Late, Late Show” (11:37 p.m., CBS).