The number of uncertified teachers in the city is among the highest.
Only the uncertified teachers, she said, could be removed and replaced.
"There's no question that we have a high number of uncertified teachers," he said.
Any increase in uncertified teachers could hurt a superintendent's evaluation.
The city has more than 10,000 uncertified teachers in its schools, well over 10 percent of the total.
That program would provide uncertified teachers up to $2,000 each to complete their required course work.
Board officials said they could not confirm the union's figures on uncertified teachers.
Students from schools with the most uncertified teachers ranked at or near the bottom.
Many of those people were uncertified teachers who have repeatedly failed the test.
That change comes in part because of the schools' increasing reliance on uncertified teachers.