Stewart said Friday that she was "hurt" that she couldn't continue to help those who are prepared enough to bypass school and go to college.
"Maybe one day God will bless me to restart the program," she said. "It's a shame that you got people who are so brilliant, and they just need to go to the next level. But maybe I can do it again, and do it the right way."
Tierney said the diploma program at Crooked Places Made Straight spread among her foster-care youths by word of mouth, and she had received no evidence in the last year and a half that the department shouldn't offer it as an option.
She added that she did not refer foster care youths to Crooked Places Made Straight — though the department paid the $500 fee — and would not restrict them from attending the school because they are old enough to make their own decisions.
"I am a champion of my older youth … to have access to education," she said. "The paths for each of them is different."
Tierney acknowledged that the department's decision to provide and fund the option for students to obtain a diploma in a day is controversial, but said she had taken "a longer view."
When she took her post in 2007, she said, the only obligation she had for older youths in foster care was making sure that they knew how to sign up for food stamps.
"If that's the best we can do, then shame on us," she said. "If Crooked Places Made Straight means they could go to college and choose what they want to do with their lives — then yeah, I'm OK with that. Beats the heck out of food stamps."