The National Endowment for the Humanities yesterday announced awards of more than $66 million in grants for educational and cultural projects that represent the culmination of NEH chairman William J. Bennett's "back to basics" drive.

"The NEH under Bennett is now supporting excellent work in the basic humanities disciplines like history and English," said Terry Krieger of the NEH public affairs office. The grants, he said, "reflect the commitment of the endowment and Bennett to educational effectiveness and cultural seriousness."

Bennett, who has been chairman for 21 months, introduced new education grant guidelines last year to encourage improvement of introductory humanities courses in secondary schools and colleges and to teach teachers. Many of these grants are the fruits of those guidelines.

"We're sharper around the edges." said Bennett. "Our work in education is a lot clearer and more focused. There's much more emphasis on the basics, less on experimentation and innovation for innovation's sake. Subject matter is what we're doing--not technique. It's not a thousand and one things. There's more coherence to what we're doing."

In the past, said Bennett, proposals were vague or too broad. "You had some proposals that were neither fish nor fowl," Bennett said. "These multimedia, multilanguage, multifaceted traveling humanities carnivals--it's hard to find out what they were about . . . What we're doing may not have as much zap appeal, but it's more substantial and more practical."

Among the awards:

* 51 summer seminars for secondary school teachers. The seminar program, designed to give secondary school teachers a chance to study humanities texts, was enthusiastically received, according to the NEH, when it started this past summer with 15 seminars. More than 2,500 teachers applied for 225 places, the NEH reported.

* $110,000 grant to WGBH in Boston to write and produce 13 half-hour radio programs dramatizing classical, biblical and near eastern myths for children.

* $42,773 grant to Spelman College in Atlanta for library acquisitions that will function as resource materials for the college's new required course on world civilization.

* $230,830 grant to Georgetown University to hold a national institute next summer to prepare elementary school teachers to teach Homer's "Odyssey."

Will elementary school students read the "Odyssey"?

"Not in Greek, but they can make it through the 'Odyssey,' " Bennett said. "Maybe a children's edition. They have to start somewhere."

Bennett added, however, that some of the new grants still fell into familiar categories. "We've got your usual suspects," he quipped, "the collaborative group of scholars working on encyclopedias, people running seminars for college teachers. Nothing changes about that."

Since Reagan appointed Bennett, the NEH chairman has openly criticized grants and proposals for not being good enough. In March of 1982, several months into the job, he said that the NEH was beset by "grade inflation," referring to proposals given rave reviews by panelists but given only adequate marks by Bennett. The following year he said that NEH has had "too much money in the past," which has led to problems like "projects that shouldn't have been funded being funded."

He has made no secret of his dislike for the "neither fish nor fowl" grants, and he exploded a year and a half ago when the Wisconsin Committee for the Humanities (which gets funding from NEH) helped fund a documentary on Nicaragua--"From the Ashes"--which Bennett called "a hymn to the Sandinistas" and "a propaganda piece."

In an age when colleges and universities are offering preprofessional courses, Bennett has encouraged educational institutions to strengthen their humanities departments and has said the NEH would try to promote traditional teaching.

The grants announced yesterday will be awarded from the regular funds allotted to the NEH for the fiscal year 1983 and the coming fiscal year, which begins next month.