The Tuition Tax Credit Act of 1977, as the bill co-sponsored by Senators Robert Packwood and Daniel Moynihan is called, is full of good ideas. That, alas, may be its political problem.

The philosophical purpose of the bill is to beef up the private educational sector, unquestionably a good idea. The practical means to be this end is the creation of a federal income tax credit; that's a good method of subsidy, and so the tax credit is a good idea. The credit, futhermore, could amount to as much as 500 for the tuition expenses of an individual or spouse or dependents: surely that's a generous enough sum to influence choices in favor of private education, and so the 500 is a good idea. Where, then, are those ideas that constitute a political problem.

They lie in a sentence concerning eligibility: "Any part-time of full-time student who attends an elementary or secondary school, or college or university is eligible for the credit." And it requires little discernment to understand that here the Packwood-Moynihan bill effectively would encourage private elementary and secondary education.

These are good ideas, but they are also mines likely to be detonated when debate on the bill commences in January. The good Senators Packwood and Moynihan likely will be charged with trying to encourage white flight, wreck desegregation, and generally discombobulate race relations.

Nc. Senators Packwood and Moyniham had better salvages their bill before it gets savaged, and the way to do that, obviously, is to edit out of that eligibility sentence the words "any elementary or secondary school." Perhaps in time the fevers on race and education will run their course, and someone - perhaps these same senators - can propose a tax credit that would perk up private elementary and secondary education. But for now, poliitcs dictates the possible - encouragement to private higher education - still would be quite an achievement.