OF, BY AND TFOR THE CHILDREN : On Nickelodeon series, the high school frosh has something to laugh at

High-school freshmen sure have it bad.

One minute they’re fearlessly cruising the halls of junior high and the next they’re groveling pitifully at the feet of juniors and seniors. Outside of hiding in a closet until sophomore year, what’s an underclassperson to do?

Maintain your sense of humor, says “Welcome Freshman,” a new half-hour comedy series on Nickelodeon. Set in fictional Hawthorne High, in Anytown, USA, the series follows five freshman characters as they share the harrowing experience of being at the bottom rung of the high-school ladder. Nickelodeon says the show is like “Saturday Night Live” for kids, blending narration with comedy sketches depicting the characters’ fantasies, fears and experiences. The producers call it “skituational comedy.” We say, if it gets you through the first semester, it’s done a great job.

MORE KIDS’ SHOWS

Those who elect to spend the President’s Day holiday lazing around in front of the tube will appreciate Nickelodeon’s five-hour marathon of animated tales. Included: “Puss ‘N Boots,” noon-1 p.m.; “King Grizzlebeard,” 1-1:30 p.m.; “Briar Rose,” 1:30-2 p.m.; “Wind in the Willows,” 2-3 p.m.; “The Adventures of Tom Sawyer,” 3-4 p.m. and “Peter Pan,” 4-5 p.m.

You could interpret it as a thinly disguised commercial, or you could lighten up and consider “The Muppets at Walt Disney World” (Monday noon-1:00 p.m. and Saturday 6-7 p.m. the Disney Channel) a free trip through the Magic Kingdom. For all ages.

The swashbuckling “The Adventures of Robin Hood” (Monday 10 a.m. -noon TBS), starring Errol Flynn and Olivia de Havilland) isn’t specifically a children’s movie--just a superb version of the classic legend. Kids probably won’t mind that it’s colorized. For ages 10 and up.

The animated “Puff the Magic Dragon” (Monday 9:30-10 a.m the Disney Channel) hearkens back to the dark ages of the 1960s, when Peter, Paul & Mary sang of the mythical creature who lived by the sea and frolicked in the . . . well, you know the song. For 4- to 8-year-olds.

“Dear Lovey Hart, I am Desperate” (Monday 4-5 p.m. Showtime) is the story of a high-school student whose newspaper lonely-hearts column is wildly popular . . . until a reader lands in the hospital. For 12- to 17-year-olds.

Disney characters Goofy and Ludwig von Drake pursue hard bodies on “In Shape With Von Drake,” (Tuesday 8- p.m. the Disney Channel) in which they bumble through calisthenics and tumble through various sports and games. For all ages.

Another dinosaur-themed episode of Nova, “T. Rex Exposed” (Tuesday 8-9 p.m. KOCE; Saturday 7-8 p.m. KCET), heads to Montana to record the excavation of the first nearly complete tyrannosaurus rex skeleton found. For ages 10 and up.

BULLETIN BOARD

To help answer kids’ tough questions about the Persian Gulf war, PBS offers a six-page discussion guide “Kids Ask About War.” Parents should send $1 to Kids Ask About War Guide, PBS, 1320 Braddock Place, Alexandria, Va. 22314. Teachers or organizations wishing to distribute the guide should contact the PBS Elementary/Secondary service at (703) 739-5145 for a clean copy and reprint permission.

The Disney Channel is now accepting applications from elementary and secondary school teachers for its second annual American Teacher Awards, to be telecast in the fall. The program honors excellence in 12 categories of teaching as voted by a committee of members from various educational organizations. Winners and their schools receive cash honoraria.

For applications, write The Walt Disney Company Presents the Amerian Teacher Awards, P.O. Box 9805, Calabasas, Calif. 91372. Applications must be postmarked no later than March 22.

“Welcome Freshman”; Premiere: Sunday, 7-7:30 p.m.; regularly schedule: Saturdays at 6:30 p.m. and Sundays at 1:30 p.m. Nickelodeon. For 11- to 15-year-olds.