Say what you will about public schools, but the teachers are, by and large, dedicated to their students and their jobs.

Witness the lengths to which Mr. Kotter went to defend and aid his Sweathogs. Or recall how Mr. Feeny doled out life advice to student and neighbor Cory Matthews, always there when he needed a little guidance.

Mr. Schuester was more than a glee club coach, he was a mentor, father figure, advocate and friend. Miss Day loved her kids so much she brought them to her apartment for some hand-bell choir rehearsal.

Prez, aka Mr. Pryzbylewski, was a far better teacher than he was a cop, all his skills located in an analytical brain; he set out to get to his kids before the Baltimore criminal drug trade got to them first.

Deep down, though she only shows it on rare occasions, Mrs. Krabappel really cares about Bart Simpson. And Mr. White saw enough promise in Jesse Pinkman that he asked him to be his business partner.

OK, wait. That last example may not be the best. Yet you can’t deny the teacher-student bond between Mr. White and Jesse was strong.

OK, wait again. Those are all fictional TV teachers, not the real ones we had as kids. (The shows and teachers references, in order of appearance, are “Welcome Back, Kotter” and Gabe Kaplan; “Boy Meets World” and William Daniels; “Glee” and Matthew Morrison; “New Girl” And Zooey Deschanel; “The Simpsons” and the late Marcia Wallace; “The Wire” and Jim True Frost; and “Breaking Bad” and Bryan Cranston.) But we’ve all had teachers in our past who have inspired us, helped us through a tough spot, made a subject come alive, or showed us how we matter.

In NBC’s new comedy, “A.P. Bio,” the new teacher of the titular subject at Toledo, Ohio’s Whitlock High School does none of those things.

Oh, Jack Griffin might accidentally inspire some of his honor-roll kids with his unorthodox approach to teaching biology, which is, in fact, not teaching biology at all. Griffin, a former Harvard professor of philosophy, who lost out on his dream job, sets his students to destroying his academic rival.

Griffin played by Glenn Howerton is the teacher who makes it clear he has no interest in being a high school teacher; he treats his new position with little seriousness to the chagrin of Principal Durbin, played with classic exasperation by Patton Oswalt. Howerton, a veteran of the nihilistic, anything-goes FXX sitcom “It’s Always Sunny in Philadelphia,” lets loose here, as he often does on “Sunny.”

His fellow teacher colleagues are at first impressed with his Harvard background, then appalled by his blasé attitude. Or perhaps they secretly wish they could speak their true feelings ... nonetheless, they are the professionals and he is the aberration.

“Sunny” has prepared Howerton well for this leading role, a no-holds-barred, singularly focused revenge artist with a strong contempt for those he believes are beneath him, which seems to be everyone else. “A.P. Bio,” which counts Seth Meyers and Lorne Michaels as executive producers, has a special preview at 7:30 p.m. Thursday on Ch. 15; it returns for its official premiere on March 1.

Music showcase: The award season carries on with “The 60th Annual Grammy Awards,” hosted by James Corden, Sunday. Scheduled to perform are Elton John, Miley Cyrus, Khaled, Kesha, Lady Gaga, Childish Gambino, Kendrick Lamar, U2, Bruno Mars, and many more. The show also plans a premiere of director Spike Lee’s short film, “NY Stories,” which features artists sharing musical memories of the city; and a tribute to those victims of gun violence at live music shows over the past few years. The tribute will include three performers – Brothers Osborne, Eric Church, and Maren Morris – who were part of the event in Las Vegas that ended in tragedy. The Grammys air live from New York’s Madison Square Garden at 6:30 p.m. Saturday on Ch. 3.

The pre-game starts now: In anticipation of the Super Bowl, CBS will be airing “Super Bowl Greatest Commercials 2018,” hosted by Boomer Esiason of CBS Sports and Daniela Ruah of “NCIS: Los Angeles.” The special features a look at the 25th anniversary of the McDonald’s ad, “Nothing But Net”; results of live viewer votes on the best commercials; and a sneak peek at this year’s. “Super Bowl Greatest Commercials 2018” airs at 7 p.m. Tuesday on Ch. 3.

Blast from the past: Veteran of the show and current big-time movie star Will Ferrell returns to host “Saturday Night Live” Saturday, with musical guest and current Grammy nominee Chris Stapleton. “Saturday Night Live” airs at 10:30 p.m. Saturday on Ch. 15.