As the tax season descends, it becomes a better idea than ever to read the fine print. Unfortunately, a reader of mine didn't, and she would like to alert others in case they're in the same boat.

On Dec. 7, my reader opened four accounts at Columbia Federal Savings and Loan to take advantage of a special promotion. In return, she received a raft of prizes: two TV sets, two sets of luggage, a Cabbage Patch doll and a Coleco game kit. "Pretty neat," she thought, as she trucked all the loot home.

But in January, a slip from Columbia Federal arrived in the mail. The S & L had reported the value of all the prizes to the Internal Revenue Service as income. As a result, my reader owed a whole bunch more in taxes than she had thought she would.

However, a little research shows that my reader has only herself to blame.

"We placed this information in our ad, in the brochures we handed out and people had to sign a separate card stating the value of the bonus plus interest earned on the account will be reported to the IRS at the end of the year," said Michael Millard, a Columbia Federal senior vice president. "We are required by the federal government to report any gift we give as interest on the account."

Maybe my reader forgot that she had signed the card. Maybe she didn't read it as carefully as she should have. Whichever, the rest of us should be aware that, in the eyes of the IRS, any promotional gift from any business is the equivalent of cold cash.

It's not just the tax season that's gathering steam. Ditto the reunion season. Here are some of the latest:

Providence Hospital School of Nursing, 1940 -- forming. Call Annie McGuigan Williams (567-3063).

La Plata High School, all classes -- Silver Anniversary Reunion, March 24, noon to 6 p.m. Further information: 735-5510.

Herndon, 1975 -- Set for Aug. 24. Call 573-3212 weekdays.

High Point, 1965 -- June 15. Call Pam Winters Jones (345-9046), Paula Miller Jacobson (340-1181) or Ruth Wagner Wexler (251-3723), evenings only.

Roosevelt, 1935 -- forming. Call Donna (347-5141).

McLean, 1975 -- forming. Call Jim Tucker (938-2080).

Central High, 1935 -- June 8, Holiday Inn, Silver Spring. Further information: Jean Lowe Berger (881-7404) or Kitty Handiboe (262-1488).

T.C. Williams, 1975 -- aiming for summer. Call Cheryl Hanback (998-7924).

Montgomery Blair, 1955 -- forming. Call Marian Bartlett (933-8798) or John Donaldson (774-4394).

Falls Church, 1975 -- forming. Call Archie Payne (281-2471).

We'd better settle this one fast. A family feud is brewing.

"I need one correct answer," writes Michelle L. Hopkins of Northwest. "Do you have to be over 13 to go to a PG-13 movie? And if you do, how are you supposed to prove it without identification? (I'm 16 and I don't have any ID) . . . .

"In the movie directory in the Style section of The Washington Post, there are explanations of the ratings. For PG-13 it says, 'Parents should give guidance for children under 13.'

"I think that means if you are under 13 you can see the movie. So does my Mom. Some of my friends say no. A magazine I read said no. My brother said no, but he's only 10 and I don't listen to him, anyway. Will you please print the answer in your column?"

Here 'tis, Michelle, from the national guidelines set by the Motion Picture Association of America:

PG-13 means that "parents are strongly cautioned to give special guidance for attendance of children under 13." This does not mean that children under 13 will be barred from the theater. It dumps the whole question into the laps of parents. It also means that your question about identification shouldn't apply. If the theater can't bar you, it shouldn't have any reason to ask you to prove your age.

So there's my favor to you, Michelle. Now do one for me.

Tell your brother that all is forgiven. And promise me you'll listen to him once in a while. I'll settle for odd-numbered Sundays or every third Tuesday night for starters. But give the kid a G-rated break, huh?

Cutie from Bill Sullivan of Silver Spring:

Question: What is the plural of "wife?"

Answer: Trouble.