A proper stocking should contain wondrous things. Crayons and toothpaste can fill the cracks, but a real stocking contains things a child has never held in his hand before--small treasures from faraway places, smooth surfaces to feel in one's pocket, things to wonder about. The trick is to create this miracle with limited time and money.

If you have only one morning to spend on such fripperies, spend it on the Mall. Culling the Smithsonian Museum shops, you will find a plethora of good things at reasonable prices.

The Natural History Museum offers a flocked triceratops -- like the Mall's that children climb on -- for $3. A little bag of petrified wood sells for $1.50; specimens of pale pink halite, $1; dinosaur erasers, 20 cents; dinosaur buttons, $1. Halved geodes or silky slices of polished agate are $1.50 each; pocket microscope/telescopes the size of a pen, $1.50.

At the Museum of American History small corn husk dolls will conjure up Little House on the Prairie for just $1. A dollar will also get you a handful of lustered "chinas," opalescent marbles that bring back memories of patched jeans and empty lots. Larger, fancy marbles (like the multicolored leaf) are 45 cents each.

There are black and gold tin whistles, made in England, $3.50 (be sure to read the guarantee!). For $4.50, a sun-powered radiometer can whirl away on your child's windowsill. Almost anything your heart desires in the way of dollhouse miniatures also is available here: a tiny lollipop, 50 cents, or a harp for the dollhouse music room, $10.50.

The shop one always seems to forget is in Arts and Industries (between the Castle and the Hirshhorn): 4-inch sundials with instructions, $5; Chinese fans, 65 cents; Australian boomerangs, $10.

Aside from the Smithsonian shops, some other stocking-stuffer sources:

* Pier 1, for treasures from the deep. Seashells start at 3 cents and go to about $5. Cowrie shells are 59 cents; sea biscuits, 99 cents; a bit of coral, $1.99; a package of two small sponges, $1.99; heaping bowl of Japanese river pebbles, 99 cents.

Brass bells from India start at 29 cents; wooden Jacob's ladders (remember those?) are 69 cents; enough chopsticks to share with the whole family, 79 cents. Wooden three-dimensional puzzles (spheres, cylinders, cubes), $1.99. How about a pheasant feather?

* Sullivan's, Wisconsin Avenue. Rainbow-leaded pencils for 50 cents; invisible ink pens, $1.50; alligator-shaped tin "cricket," 49 cents; Italian stacking crayons, $1.

* The Christmas Attic, Alexandria. Chocolate finger rings, cars, pocket knives and penguins, 45 cents to $3. Three-dimensional butterfly barrettes are $1.25; penguin-shaped scissors, 65 cents. Real crystal teardrops to hang in the window as rainbow-makers come in a variety of shapes (and are an excellent choice for shut-ins as well as kids), $2.75 and up for a proper size. This one will take you back: straw Chinese finger traps for 15 cents.

* Heinly's Country Store, Alexandria. Maple sugar toy soldiers, maple leaves and liberty bells. Prices start at 50 cents.

* New Energy Sources, Tysons Corner. Tiny magnetic thermometers, 99 cents; stick-on window bird feeders, $2.79; Isoso 3-D construction kits starting at $2.49.

* The Red Balloon, Georgetown, for some things from your past. Trick coin box, $1.50; three-piece propellers, 25 cents; three big rainbow crayons, $1.50. And this is where you can find the tiny little wooden bird calls that are such fun to turn and squeak, $3.98.

* Bowl and Board, Georgetown, for good wood-smelling things. Mahogany letters, $1 each; wooden ark animals, $1.50 for a giraffe; $2.50 for a moose.

And don't overlook more routine stores. Radio Shack is reputed to have the best magnets in town, 18 cents each. Coin shops and departments could sell you a real Roman coin that clinked around inside a purse at the market 2,000 years ago. A rhinestone tiara from a dance-supply store will turn any little girl into a princess. The grocery stores have amaryllis bulbs.

Remember, it's the retailer's ideal to be sold out of practically everything by January inventory. Save precious time by calling first if you're tracking down a particular item.

Have fun but use caution. You can walk out with a bag small enough to fit into purse or briefcase and be $75 poorer if you don't pay attention. If you've no one else to stuff for, why not create the most wonderful stocking you can imagine and donate it to a charitable agency?