When some people give a party, it's for a purpose. One friend gave a dance to celebrate her birthday. The men donned dinner jackets, the women their best gowns, to waltz under a spinning, mirrored ball and to fill their glasses from a champagne-spouting fountain.

Now that friend has announced it is time for a Spring Prom, and her guests have begun to rummage in the attic for merry widows and stiffened petticoats. Their thoughts are of a prom without pain, without the fear that the boy in Latin class will ask the redhead sitting in the last row, or that the purple dress will be ruined by a corsage of red roses.

Proms, like first kisses, come at a time when we're too young to enjoy them. Instead of feeling a sentimental nostalgia at the springtime sighting of youngsters in pastel dresses and white dinner jackets, it is well to remember that the overriding fear (female) of the evening was that the pastel dress would fall down, and (male) that it wouldn't.

Now, when we are older and wiser, when it is economic indicators whose fall we fear, we can properly enjoy a spring dance. Depending on the size of your house, the number of friends and your commitment to recreating the adolescent experience, you may want to sponsor this party with others. Get enough together and you can rent a hall or, if your faith in God and the weatherman is strong, rent an outdoor dance floor, string Japanese lanterns from the trees and hold the prom in your yard.

If you truly want to make the trip back to your teen years, refreshments will pose no problem. Tell people to bring their own liquor and hide it in the glove compartments of their cars. If you draw the line at such a reversion to the past, you can install a champagne fountain. Because the wine is not improved by its endless trips through the fountain, some less-traveled tipple can be held on ice and served to people tired of filling their glasses from the spray.

Traditionally, there is the after-prom breakfast, either in a restaurant with the male half of the couple nervously examining the right side of the menu, or at someone's house. If the prom is a joint venture and cost is not important, you can hire a caterer to serve scrambled eggs at midnight. Or, if the dancers are not too numerous and the kitchen not too small, you can appoint a Food Committee to invade the kitchen and make the eggs. No self-respecting prom would be without at least one committee.

The Decorating Committee will, of course, have long since settled the argument over whether the room is to be hung with crepe-paper streamers or whether the budget will stand the rental of a mirrored ball, blinking brightly under the beam of a pin spotlight.

Music can be provided by records or by a live band. (Check the "Musicians" listing in the Yellow Pages, and make sure you know what you're getting; what is music to one is din to another.) A disc jockey will come to your party, set up his equipment and play the music of your choice nonstop for 3 to 4 hours.

Some of the firms offering deejay services:

Bristol Sounds (345-0200). Minimum of $175 for three hours, $25 an hour after that. Collection of 10,000 titles runs from the '20s to the present.

Burg Music (737-9111). A disc jockey to fit your needs at $150 for four hours.

Disc Jockeys, Inc., Baltimore (301-686-9096). $120 for four hours of music during the week; $250 on Friday and Saturday nights.

The D.J. Connection (772-2569). $40 an hour (each booking has a 3-hour minimum) Sunday through Thursday before 6 p.m.; $50 an hour weekdays after 6 p.m.; $60 an hour on Friday and Saturday nights.

Washington Talent Agency (468-5700). Three hours of music on Saturday nights, $135 to $185 depending on the experience and record collection of the disc jockey; $110 to $185 at other times.

Be sure to include at least one Golden Oldie for the chaperones.