IN PROPOSING to liberalize regulations that limit child labor, the administration has raised questions quite different from those that surrounded the enactment of early child labor laws. The question in this case is not so much what kind of work children should do as how much they should do.

The notion of amending the child labor laws should not in itself be grounds for great anguish. The marketplace has changed a good deal in the 44 years since the laws were last overhauled. Letting 14- and 15-year-olds do hand-washing of trucks and vans when they are already allowed to wash cars should not be reason for concern. And prohibiting a generation raised on electronic games from operating cash registers or data-processing machines is surely anachronistic--as long as these are physically separated from hazardous chemicals and dangerous machines as the regulations would still require.

A much more important issue is raised, however, by those parts of the regulations that would allow 14- and 15-year-olds to work longer--and later-- hours. This was the change most sought by the amusement and fast-food industries, which represented the major moving force behind the proposed regulations. Allowing young teen-agers to work until 9 on school nights and 10 on weekends and vacations opens up a whole range of job opportunities in restaurants and amusement parks that were previously reserved for older youths and adults.

The longer hours would certainly be popular with the many children who are anxious to earn pocket money to support the increasingly expensive tastes of modern youth. And some parents would also prefer to have their children working rather than hanging around on the streets--unless they simply postpone that activity until after work hours. But--and remember we are talking about 14- and 15-year-olds--isn't there something else besides 24 hours of paid work a week that both parents and the law should be encouraging young people to do? What about homework?

The case for expanding job opportunities for young teen-agers would be a good deal more persuasive if an argument could be made that American youths were wearing themselves out at their books or that the labor market was in dire need of extra hands. But educational standards keep falling, and there are millions of older workers--out-of-school youth and unemployed adults--desperately seeking any job opening no matter how menial. Why encourage employers to hire 14- and 15-year-olds when half a million black 16- and 17-year-olds can't find work and millions of older workers have been permanently displaced from their jobs? Regulations shouldn't be written with only the short term in mind, but the employment situation for these groups won't get better soon.

Finding ways to link school learning with on-the- job experience can help many youths find jobs more easily later on. Updating labor laws that keep 16- and 17-year-olds from many no-longer-hazardous occupations could also help school dropouts. The proposed regulations, however, address neither of these problems and perhaps create some new ones.