As the school year draws to a close, the summer-job outlook for American teen-agers is the brightest it has been in several years. ''The summer of '84 will be a good one for summer jobs,'' says William Kolberg, president of the National Alliance of Business (NAB), an independent group that promotes and manages summer employment programs for disadvantaged youth. For disadvantaged youth alone, government and private experts expect companies to offer as many as 80,000 more jobs than in 1983.
Despite increased hiring by business, experts say there still won't be enough jobs. About 2.9 million 16- to 19-year-olds flooded the job market between April and July 1983, and a similar influx is expected this year.
''The ability of the economy as a whole to provide jobs for teen-agers is not terrific,'' says Nathan Weber of the Conference Board, a business research organization that recently issued a report on the summer-job outlook.
The problem is worst in industrial cities like Detroit, where a high overall unemployment rate makes finding jobs for teens especially difficult, Mr. Weber says. New Detroit Inc., a civic group that arranges summer jobs and other services for local teen-agers, expects to place only about 400 disadvantaged youths this summer. That is about the same number it placed in 1983 and is far below the demand for jobs.
In March, teen-age unemployment stood at a seasonally adjusted 19.9 percent rate, vs. a jobless rate of 7.8 percent for the civilian population as a whole. Black teen-agers suffer unemployment rates more than twice as high as white teens. April unemployment figures, slated for release today, may decline but by no more than 0.01 or 0.02 percent, according to Robert Gough of Data Resources Inc., a forecasting firm.
The economy's continued gains and the improving overall employment outlook are key reasons for the rosier summer job picture, experts say.
''An economy that has an unemployment rate in the seven (percent range) provides vastly better opportunities for our young and inexperienced workers than does an economy with unemployment of 9 to 10 percent,'' says Donald Straszheim, vice-president of Wharton Econometric Forecasting Associates.
As fewer of the nation's more experienced workers are forced to compete for entry-level jobs, prospects improve for job-hunting teens. And fatter profits and the return of laid-off employees make companies more willing to consider hiring summer help, although executives are hiring carefully.
Employment prospects for youth also look better because of recently enacted federal tax measures designed to encourage hiring of 16- to 19-year-olds. The Targeted Jobs Tax Credit (TJTC), which took effect in 1983, cuts the cost of hiring a disadvantaged youth at the minimum wage to just 50 cents an hour.
Now that companies are more familiar with the credit, NAB's Mr. Kolberg expects companies to offer as many as 100,000 TJTC jobs this year, vs. 33,500 in 1983. Government analysts say Uncle Sam will fund 818,000 summer jobs in the various states in 1984, about 5,000 more than in 1983 but fewer than during the final summer of the Carter administration.
In addition, the Office of Personnel Management will put about 42,000 teen-agers on the federal payroll this summer, roughly 7,000 more than last year. Finally, businesses are expected to hire as many as 200,000 disadvantaged youths not covered by TJTC, an increase of roughly 15,000 positions over 1983.
These figures cover disadvantaged teens. Firms also will hire more middle-class youths, but there is no central clearinghouse that tracks such hiring.
Conference Board researcher Weber says that more effective job-hunting efforts by local groups - spurred by changes in federal law - are another important reason teens will be given more jobs this summer.
For example, officials at New York City's highly organized Summer Jobs '84 program expect to come up with 25,000 private-sector jobs this summer, vs. 19, 000 last year.
Despite the improved youth-hiring outlook, the total number of jobs offered will fall far short of the need. ''Virtually every kid in the city is looking'' for a job, says Richard F. Halverson, program director of Summer Jobs '84. The city expects to receive more than 100,000 applications.
UNEMPLOYMENT RATE FOR TEENS 16-19 Both Black White sexes males males 1974 16.0% 31.5% 13.5% '75 19.9 35.2 18.3 '76 19.0 35.1 17.3 '77 17.8 36.6 15.0 '78 16.4 34.0 13.5 '79 16.1 31.3 13.9 '80 17.8 34.4 16.2 '81 19.6 37.5 17.9 '82 23.2 44.0 21.7 '83 22.4 45.0 20.2 Source: Department of Labor, Bureau of Labor Statistics