Tax credits for private-school tuition have not captured enough supporters for passage in Congress. But the idea has enough friends to keep it alive. Its most important friend, President Reag'n, just back from his Far East trip , wasted little time before telephoning Senate Finance Committee chairman Robert Dole (R) of Kansas, urging action. And the Senate, just days before adjourning for the year, is giving the proq and cons one more airing.
''After reviewing the findings of the Commission (on Excellence in Education) with great interest, I am more convinced than ever that passage of tuition tax credit legislation is needed now,'' said President Reagan in a letter that Senator Dole made public as he introduced the latest version of tuition tax credit legislation.
Under the Dole proposal, parents could receive up to $300 in tax credits per child for sending child2en to private primary and secondary schools. In answer to charges that such a plan would subsidize an exodus of white students from public schools, the bill excludes tuition to schools that discriminate by race.
The newest bill also would grant refunds even to those parents whose taxes are too low to enable them to use a tax credit. Total cost of the program, according to Senator Dole, would be $800 million per year.
Opponents of tuition tax credits are making it clear that they will block the bill, and they will have little trouble doing so, since the Senate has other legislation it must complete. So far, opponents have halted even a motion to take up the bill.
''We are engaged in a debate of one of the most fundamental policy questions to come before this body, I believe, in this century,'' Sen. David L. Boren (D) of Oklahoma told his colleagues. He added that the cost might be $1 billion per year and the result would be ''a little more . . . skimming off the top'' of public schools those students who come from better-educated, higher-income families.
Speaking for the plan, Sen. John P. East (R) of North Carolina said, ''When Johnnie and Jane come home and they obviously are not learning to read and write'' parents ''make the financial sacrifice'' to send them to private schools.
''All wewould be doing here is considering the possibility of giveing them modest tax relief he said.
The bill still could be passed during the 1984 session of Congress. At the least, it will provide an issue for the presidental.