`Twas 20 days before Christmas and all through the Square, students were shopping for mom, pop and Aunt Claire. Break out the credit card, spend your last penny, buy gifts for the Yard and purchase a'plenty!

A is for Alcohol. For the discriminating palate, the five-year-old Moet and Chandon champagne lists for $30.49 at the Harvard Provision Shop (94 Mt. Auburn). For smaller wallets, they offer Cavas Hill champagne at $6.99. If you're looking for that distinctive, and yet inexpensive, alcoholic gift, there's always Harvard 350th commemorative white wine for $6.50.

B is for Bears. No holiday season would be complete without a few cuddly creatures. Calliope (33 Brattle) sells three inch high antique bears, for just $3. If money is no object, check out their huge Paddington for $350. For those who are tired of intellectual dining hall conversation, there's always the $89 animated Teddy Ruxpin at FAO Schwarz (40 Newbury St.).

C is for Cosmic Awareness. To reach your karma, Shambhala Book Shop (58 JFK) sells incense, meditation music, and a complete range of books on mysticism and the occult.

D is for Dancing Lessons. 'Tis the season of formals, and if your dancing steps could use a little brushing up, Arthur Murray Dance Studio (364 Boylston) offers an introductory package of three lessons for $10. But if your partner needs more guidance than that give him or her Dance World's extensive $360 12-week course in ballroom dancing.

E is for Evening on the Town. For a swanky affair, treat your date to cocktails at the Ritz (15 Arlington), dinner at The Four Seasons (200 Boylston), and orchestra seats at the ballet. Total cost, including a nightcap of Dom Perignon '77: $350.

F is for Fortune Tellers. See the future and recall the mysterious and adventurous gypsy life of the past with a visit to Arsenic and Old Lace (1743 Mass. Ave.). One look into a lead crystal ball will cost $10, while a tiny peek into a fine quartz orb could run upwards of $400. Tarot cards, ranging from $6 to $80, are also available for those inclined to soothsaying.

G is for Glitter and Glamour. If you want to add that sparkle to your evening, you can buy black stockings with a rhinestone seam for $12 at At Saks Fifth Avenue (Prudential Plaza). Rhinestone jewelry ranges from $28 for a choker to $10 for a tiara at Reddog's (1737 Mass. Ave.). If you want to go all out, Atalanta Antiques (1700 Mass. Ave.) sells a beaded and chiffon flapper dress for $300. For the finishing touch, Chanel No. 5 perfume, a mere $175 per ounce.

H is for Harvard. You know all your relatives are dying for an article of clothing with that name on it. The Coop (1400 Mass. Ave.) sells a crimson Champion sweatshirt for $45 or a striped scarf for $25. A pair of Harvard booties at $8.50 will make the perfect gift for the baby in the family. Feeling Scrooge-ish? Buy a 29-cent Harvard pencil or a 90-cent bar of Harvard soap.

I is for Ice Cream. Even though it may be snowing outside, no one can resist ice cream. Especially when it's in the form of an ice-cream cake from one of the many parlours in the Square. Emack & Bolio's (1310 Mass. Ave.) pies range from $8.95 to $17.95, while Steve's (31 Church) $8.95 concoctions serve between five and six.

J is for Jungle Gear. For a special friend who truly enjoys the company of elephants, snakes and water buffalo, Banana Republic (Charles Square) offers a pith helmet for $24. In case you're going into Africa, you can spend $42 on pleated front, lightweight cotton chinos at Banana Republic. For those who yearn to take to the skies, an authentic World War II flight jacket, $259, will take you up, up and away.

K is for Kites. To indulge those soaring spirits further, check out the goods at Outermost Kites (Faneuil Hall). For $4.95 they'll sell you a dragon kite with an 80-inch streamer tail. A limited edition Sanyo rokkaku kite, complete with Samurai warriors, sells for $300.

L is for Leather. Nothing can beat the feel of raw leather against your skin. Pennsylvania Company (28 JFK) has black leather skirts for $220, skinny ties at $7.00, and, for the rugged individualist, a variety of jackets ranging from $190 to $500. And for the upwardly mobile, The Coop sells leather attache cases for $50-$200.

M is for Memorabilia. This is the year to put Harvardiana under the tree. The Harvard Shop sells pure silk ties bearing the 350th logo for $25 and corduroy baseball caps for $13.

N is for Nightshirts. You can't have visions of sugar plums unless you're wearing a cozy nightshirt. Brooks Brothers (46 Newbury) offers a traditional 100 percent cotton flannel sleepshirt for $30, and the Banana Republic sells their Artisan's Nightshirt for $36.