With the arrival of another school year, what parent doesn't dread the imminent influx of kids' Important Collectible Papers? The family historian knows that it's only a matter of months before the ICPs take over -- first the refrigerator door, then the kitchen junk drawer, the bookcase, desk drawers, end tables . . . aaagh!

But only a heartless cad could contemplate disposing of Jacob's first nursery-school painting or Rachel's clown name tag from the first day of kindergarten. And what about second-grader Aaron's first autobiographical essay? Years hence, the budding author may be inspired by that work's rare insight. "Three apples, colored red" by Joanna, the four-year-old mathematician, is also noteworthy, as is her revealing family portrait.

There's no stopping the influx of posterity-worthy papers -- they will come, whether pinned to your preschooler's back or totebag, or proudly clutched by the grade-school genius.

You can't just throw away ICPs. First of all, you might get caught: "Mommy, what's my dinosaur drawing doing in the trash?" Besides, these mementos are invaluable treasures of youth.

What to do? Here's the systematic solution this family historian and mother of four devised. In four easy steps, kids' Important Collectible Papers are shown, stored, sorted and finally incorporated into a scrapbook.

Old-fashioned scrapbooks are the ideal medium for organizing and preserving kids' memories: They're cheap, durable and, best of all, the kids can do most of the work themselves. Here's how to do it: 1. The Show: Kids are proud of their handiwork, and their best papers or artwork should be displayed prominently, albeit briefly, in the family showplace: refrigerator door, bulletin board, den. We tape such seasonal artwork as turkeys, Christmas wreathes and painted cherry blossoms to our front door for all the neighbors to admire. One creative friend made two large plastic clip frames to display her two preschoolers' artwork. Every two weeks, the young artists select their best art to hang in the family's dining-room gallery. More simply, you can string cord or yarn from corner to corner in the child's room and hang artwork with clothespins. 2. Storage: Right now, before school is in full swing, is the time to prepare for the crucial task of storing ICPs. Obtain a cardboard box for each child and put it in an accessible place. Everything from artwork to spelling, sports certificates to ballet recital programs and photographs to report cards can be stored in the box. As papers arrive, or after they've been displayed, add them to the box. Months later, when it's time to sort and create the scrapbooks, the papers will all be in order if you dump them out in one fell swoop. For extra chronological protection, scribble the date of entry on each stashed article. 3. Sorting: This is a thrilling parent-child project. At the end of the school year, dump the scrapbook storage box upside down in a neat pile. Voila! Instant chronological order. Next comes the fun of inspecting each item and deciding what's really worth saving. This pares down the pile considerably. But you'll beam with pride at your organization and foresight when your child shrieks with delight,"Oh! here's my cherry blossom chalk drawing! I remember when I did that. It was so hard." In past years, this valued art would have had a short lifespan in our house; now it's preserved for posterity. Allow plenty of time for sorting since kids love to reminisce. If you run out of time, simply put all the sorted papers back in the storage box until your next session. 4. Scrapbook: Creating the scrapbook is the most fun of all. Scrapbooks can be bought for less than $5 at most drugstores and variety stores. We've found them at virtually all the places that stock inexpensive school and stationery items. Try to buy a stack of filler paper at the same time. We're talking about old-fashioned scrapbooks with cardboard covers, silky strings and heavy, rough manila pages. The beauty of these string-tied scrapbooks is that they can grow to accommodate even the most prolific year's output. Just add the filler paper and tie on more string. Get some black stickum photo corners if you can find them and spice the book up with photographs. You'll need lots of glue (buy one huge size for refills and several smallest-size glue bottles for the kids to use), scissors (large and kid-size), pens, crayons and markers. Then go to it. Inscribe a fancy title page: "Rachel -- 1982 -- Kindergarten -- Bethesda, Maryland." Sprinkle on some glitter, scratch'n'sniff stickers or a favorite photo. Next, glue in name tags, A-plus spelling papers, that insightful autobiography. Large artwork, if folded and trimmed to fit, can be its own page. The same goes for thick paper projects: Simply untie the scrapbook laces, punch holes in the thick entries and re-insert. Sometimes we glue a painting over two pages and use it as background for other items. Anything goes in a scrapbook. Kids can decorate pages with drawings or border designs. But be sure to label entries and write in friends' full names for future failing memories. Even the neighborhood kids love to pore over all the marvelous trivia in their friends' scrapbooks, oohing and ahing over shared reminiscences. While a scrapbook is the ideal cure for the Important Collectible Papers syndrome, its usefulness is not limited to the school year. For the young athlete or ballerina, a career scrapbook can continue for years. Special vacations and family trips also yield enough paper to produce a vacation-issue scrapbook. Our "Summer -- 1982" scrapbook begins with our train tickets and goodbye photos. It includes scorecards from putt-putt golf games, theater programs, matchbooks and napkins from restaurants, church bulletins, drawings and games from car rides and plenty of photos. Eventually everyone begins chiming, "Save this for the scrapbook." Important Collectible Papers no longer threaten simplicity and order on our homefront. Tucked away, eventually to punctuate posterity, they have become a family asset, well worth the minimum effort involved in preserving them.

STARTING A STASH

Many stores in the area now stock brightly colored storage boxes ideally suited to this task. HECHINGER'S carries the widest assortment: blue-and-white-checked storage boxes ($2.99), under-the-bed walnut-grained boxes ($1.99), two- drawer file boxes in red-and-white checks ($12.95) and four-drawer file boxes in gray and yellow ($11.95) or floral prints ($8.95). CONRAN'S in Georgetown stocks slick file/storage boxes in black, navy and red ($4.75 to 7.75). K-MART, PEOPLE'S and other discount and drug stores also sell wood-grain cardboard storage boxes in various sizes ($2 to $5).