Household objects offer opportunities for children's play on winter days

''Mom, what can I do?'' is a cry for help heard in many households at this time of year. The weather conditions that cause school cancellations often also prevent outdoor play. Cooped up inside, parents and children are left with long days to fill.

Expensive toys, television, and electronic entertainments are not the only engrossing indoor pastimes. Every household contains a wealth of materials waiting to engage the creativity of children. All that's needed to make these days active and fun is a parent's fresh look at the resources at hand.

A quick tour through the rooms of a house will uncover some of the possibilities.

In the kitchen, supplies and equipment are not only natural props for make-believe cooking and playing store, but can also be excellent stacking-nesting-sorting toys for toddlers and percussion instruments for budding musicians. Empty containers have myriad uses: Milk cartons are quiet bowling pins to strike with a soft rubber ball. Two juice cans, when connected by a string poked through holes in the ends and knotted securely, make a walkie-talkie.

The words on boxes can be cut out and used by children to form simple sentences. Words or letters printed on Popsicle sticks can be used, too. Toothpicks present multiple possibilities. They make fanciful designs, when glued to colored paper; become make-believe porcupine quills, when stuck in a potato or apple; and offer a game of manual dexterity, when stacked crisscross on the open end of a soda bottle.

A basement can offer useful containers. The larger ones, after being cut, colored, or painted, can often be transformed into play houses, hideouts, boats, or space ships. Scraps of wood, large nails, a hammer, and (for older children) a coping saw can produce sculptures and simple constructions. Toddlers, too, often enjoy matching and screwing together such workbench supplies as large nuts and bolts, or stringing washers onto shoelaces. Even the woodpile in the garage affords hours of fort building, with some fresh air besides.

For quieter (and cleaner) play, check the sewing area. Fabric scraps, buttons , and leftover bits of yarn and trim can become the makings of puppets when sewn or glued onto discarded socks. An old stuffed toy can be ''dressed'' by sewing fabric right onto it. A safe dart board is easily constructed from Velcro scraps and cotton pompons, and a pitch-in-the-can game needs only a handful of buttons. Empty thread spools string easily on shoelaces; become makeshift Tinkertoys when combined with pencils; and, if given painted faces, become dollhouse figures.

The living room and home office contain further possibilities. Paper clips link together into necklaces, and the eraser ends of pencils offer an intriguing alternative to paintbrushes. Cardboard backs from writing tablets, when tied together, form the pages for child-written books. Printed with larger letters and cut in half, they become a letter-recognition game. And when magazine pictures are glued on them and allowed to dry, they can be cut into jigsaw puzzles.

Long pieces of wrapping or shelf paper can become the ''canvas'' for a mural or a life-size self-portrait. An adult traces the outline of the child's body, leaving all the details to be filled in.

Even clothes closets yield more than dress-up potential. Miscellaneous objects can be suspended from coat hangers to form mobiles, and empty shoe boxes with lids taped shut make light, sturdy building blocks.

And there is always the bathtub! No law says that playing in the tub is only a bedtime activity, or that equipment from the kitchen - especially sieves, funnels, spouted measuring cups, and the like - cannot be enjoyed there, too.