Parents are most often the best judges of their children's capabilities, but sometimes they underestimate what their children can do, say Dr. Richard Rubin and John J. Fisher, coauthors of ''Your Preschooler'' (New York: Macmillan, $10. 95). In their book, they offer ideas for a variety of household chores young children can learn to do or at least help with.
Cleaning up. One of the first things children learn is to pick up after themselves. According to Mr. Fisher, physical order becomes very important to toddlers as they begin to define their possessions and where they belong. By age three, children can often do cleanup themselves with minimal prodding and encouragement from parents.
The authors suggest letting a child join the parent in thoroughly cleaning a room. A preschooler can mop and sweep if he has a child-size mop and broom. Polishing furniture, the authors say, is especially enjoyable for young children. And once a job is completed, it's always important to give credit where credit is due.
Laundry. The first job children can learn here is to pick up after themselves , by putting their dirty clothes in the hamper. Children might also enjoy helping a parent load or unload the washer and dryer, helping to smooth and sort clean clothes, and put them in the proper drawers.
Mealtimes. Toddlers can begin to help in this area by clearing their own plate and cup. They can help with other dishes as they become better at it. Preschoolers can easily learn to throw away paper napkins and sponge off the table after dinner.