At some point during the year, the family cook likely will be throwing at least one kiddie birthday party. This is no small thing. Most family cooks I know go into a serious tizzy over kiddie parties. They produce much more anxiety than, say, a grown-up dinner party, because grown-ups tend to be polite, and if everything is wretched they will not tell you; and you will never know.

If adults get bored, they will, at worst, doze off, while anything can happen with a roomful of 4-year-old boys who get bored. And, bored little girls of perhaps 6 will label your party yucky and report you to their own mothers who will ostracize you socially.

Fortunately, this sort of thing does not have to happen. At about the age of 4, children seem to be magically imbued with something called party manners. This doesn't mean they suddenly have manners, but they do seem to sense the occasion, and as a group can behave much better than they do when there are only about two of them around. As a result, a party of 12 is not really six times worse than a play date, although that's what we're all expecting.

The secret of increasing the odds that things will go well is careful planning. Everything -- food, games, favors -- must be done in advance because once the kids arrive they will need your full attention. Party manners or no, as one mother put it, "If you turn your back on them, they will kill each other."

A survey of experienced mothers has turned up several useful tips:

(1) From the age of 9 up, birthday parties should be held outside the house -- restaurants, skating rinks, gyms and theaters are all likely spots. The last place those kids want to be is home.

(2) Invite only as many children as your child is years old. I have always found this impossible because my sense of festivity is too great, but it seems to work well for children who are either very retiring or very active.

(3) When the party's at home, ask one child, a best friend, perhaps, to stay later and help the birthday child cool off slowly. While child and pal quietly play with the new loot, the family cook can be quickly scraping the frosting off the rug instead of doing this while the birthday child is collapsing in a heap of post-party depression.

And now for some words about entertainment. I love the idea of expensive clowns and magicians, but they can be a flop. Three-year-olds often wail at the sight of a clown, and a magician can't hold them until they're 6 and older. To earn their money, such grown-ups tend to go on for about 40 minutes when the average kiddie attention span might be about 20 minutes.

One mother I know hired two 12-year-old neighbors to do the magic tricks; later they helped with the serving and cleanup. On rainy or snowy days, a movie borrowed from the library is a great treat, and it's better to get three 10-minute movies than one 30-minute movie. Rickety old projectors that blur and screech are of course much more fun than a videotape recorder, which is a lot like watching television.

Games should be noncompetitive until the age of 6. (Several mothers stressed this.) If a game has a winner, one child may be obnoxiously victorious while the other 11 are fit to be tied. You don't need this. One mother was so intent on this point that she handed out 22 prizes for the 22 costumes that came to her son's fancy-dress birthday party.

One game that is fun and non-competitive is a hunt -- peanuts outdoors, stuffed animals indoors. The prize is how much fun you have finding things. One generous 4-year-old I know made a game of opening the presents. Each child got to open the present he or she had brought, then everybody played with the presents until cake time. This child is no doubt headed for the diplomatic corps.

A crucial part of the kiddie party is the loot bag. The bag itself ought to be made of sturdy brown paper, the kind lunches used to be packed in, with maybe some stickers and certainly the child's name on it. (This is to ensure that everybody gets one and nobody gets two.) Don't forget to pack one for the birthday child.

Inside the bag, little gifts are far more important than candy, which can be begged anywhere. By all means avoid those fluorescent pre-packaged party favors that are expensive and cheesy. The best places to buy party favors are discount stores (little notebooks, pencils, boxes of chalk, key chains, mirrors) and museum shops (little dinosaurs, magnifying glasses, bug boxes, erasers.) If the party is small, some mothers have gone out for a helium balloon for each child with his or her name written on it.

Now, about food and serving. My children will be very old (maybe about 24) before they can sit on the good dining room chairs with all their chums. Instead, we spread a tablecloth (cloth, never paper, or a dark bed sheet will do) on the family room floor and call it a picnic. If you can do this outdoors, that's even better.

If you are serving lunch, little pizzas or peanut butter and jelly sandwiches cut small are the most popular choices. "I used to make a nice melange of sandwiches -- egg, tuna, ham -- on very thin bread, cut in pretty shapes," sighs one mother. "But all they ever wanted was peanut butter and jelly." A very experienced mom votes for juice right in the can with straws because it makes a heavy-bottomed drink, while juice in paper cups inevitably topples over.

The cake is central and should be homemade because bakery-decorated cakes are exorbitant and nobody much cares. Besides that, making a child's birthday cake gives the family cook one of those warm, wonderful feelings that cooking can bring. Sheet cakes are easier to decorate than round ones, and if you are clumsy with the squeeze tube, you can skip the "Happy Birthday" and just settle on the child's name. It is very difficult to draw GI Joe or Strawberry Shortcake on a cake, and much more effective to scrub He-Man's little feet thoroughly and plant him on top.

It is certainly okay to serve ice cream around the table right out of a box. But if you are having little girls who are old enough to appreciate it, you might press softened ice cream into a cold mold the day before, freeze it, unmold, and decorate with candied violets or real flowers on the day of the party.

Because kids under 9 don't really want an exotic feast, today's recipes are few: one for individual pizzas, and one for carrot cake, so you can sneak in a vegetable. Both can be made in advance, and the cake, in fact, is better when it is aged for a day or two. INDIVIDUAL PIZZAS (Makes 12 pizzas) 6 english muffins, split 8-ounce jar tomato sauce 8 ounces mozzarella cheese, grated 24 thin slices pepperoni (optional)

Toast the muffins very lightly to make them crisp. Spread a large tablespoon of sauce on each, and top with two slices of the pepperoni if used, then cover with mozzarella cheese. Broil 5 minutes in advance, then reheat quickly before serving. FRESH CARROT CAKE (12 servings) 1 cup butter 2 cups sugar 1 teaspoon ground cinnamon 1/2 teaspoon mace or nutmeg 1/2-1 teaspoon grated orange rind 4 eggs 1 1/2 cups fresh carrots, finely grated or shredded 2/3 cup walnuts, finely chopped 2 1/2 cups sifted all-purpose flour 3 teaspoons baking soda 1/2 teaspoon salt 1/3 cup warm water

Cream the butter and then cream in the sugar until very light and fluffy. Add the spices and grated orange rind and beat. Add the eggs, one at a time, and beat well. Stir in the carrots and nuts. Sift the dry ingredients and add with the water. Do not beat when adding the flour, but rather fold in just until it is moistened well. If using an electric mixer, do this on the lowest speed. Turn into a greased and floured 11-by-15-by-2-inch pan (or into 3 8-or 9-inch pans). Bake in a 350-degree oven for about 25 minutes for layers or 35 to 40 minutes for a sheet cake. The cake is done if it springs back when touched lightly in the center. Cool for a few minutes, then loosen from the sides of the pan, and turn out onto a cake rack to cool. Ice and cut in small pieces. CREAM CHEESE FROSTING tablespoon butter 8-ounce package cream cheese 16-ounce box confectioners' sugar 2 teaspoons vanilla

Set the butter and cream cheese out to soften, then beat together with confectioners' sugar and vanilla with an electric mixer.