An easygoing mom, the single, divorced mother wants her kids to be able to talk to her about everything.
But around this Dover household, you'd be better off getting a "D" on a report card than letting a little white lie roll off your lips.
Both her girls are honor students, the kind of teenagers who do their homework and rarely get in trouble.
After 17 years, the first and only time her oldest daughter was grounded, it was for the greatest possible offense lying.
Dishonesty lights a fire in this otherwise shy and reserved woman.
"Don't lie to me," she said. "That makes me more angry than anything."
In the same way, if you try to mess with her kids, she'll hunt you down like a lioness.
Growing up around York Springs and Dillsburg, Kitzmiller was a country kid with divorced parents which wasn't as common as it is today.
Though she was generally quiet, she was deemed "the annoying one" in Sunday school, the one who posed questions.
"I guess I just never had the faith. I never bought into it. I just always had too many questions," she said.
She grew into a person who thinks "outside of the box," she said. At 39, she wears a belly-button ring; her favorite place to vacation is Miami South Beach.
But she has created a sort of legacy.
Kitzmiller read about her local school board in newspapers during the summer of 2004. Public talk of creationism in biology classes agitated people. Her eldest daughter, Megan, was an incoming freshman and was supposed to take the biology class that fall.
At first, the issue was a joke at the Kitzmiller house, a neat rancher with two winding paths converging near the front door.
She would tell her daughters, "God, I'm gonna sue the school because I can't believe they want to bring up religion."
But the school board members wouldn't back down, "even after everyone stood up and complained about it and said, "Do you know how crazy you are for doing this?"
The controversy grew. Neighbors talked.
Kitzmiller asked a man next door whether he, too, was worried about the school board's desire to teach creationism. The conversation ended in the first suggestion that Kitzmiller was "an atheist."
"As I got more involved in this, and I realized how they were covering their tracks, I just was thinking, "What the hell is wrong with you people?"
She was apprehensive about her first visit with the attorneys.
At the law office, she ran into two other residents, and it was like being spotted sitting on the wrong side of the bleachers at a home game.
The man told her, "You didn't see us here, and we didn't see you here."
In December 2004, Kitzmiller et al. v. Dover Area School Board was filed.
Attorneys told her they listed her first because she has a good Pennsylvania-Dutch name and she was the only parent with a child in ninth grade.
The self-described "private person" was the top name on a lawsuit that would gain media attention from across the world. The couple from the lawyer's office weren't listed on the suit, and neither were several others who talked to lawyers.
There were times she was scared, more for her teenage daughters than herself.
She told the girls they didn't have to answer the phone. Sometimes when she drove home, she wondered what would greet her when she pulled in the driveway. A swarm of media? Hate mail?
One letter she received, scrawled in big letters across a sheet of yellow notebook paper, begins, "When you open your eyes in hell. ..."
One boy at school told the girls to tell their mother to "go to hell," delivering the message through a third person.
The girls and their friends who disagreed about the lawsuit agreed to disagree and get along, an achievement that escaped some adults in the community.
The atmosphere worsened as campaigning began for a hotly contested school board election and people prepared for the trial. There were nasty phone calls and confrontations in restaurants and on the streets.
After the trial started last fall, attention turned to former school board members who talked about creationism in 2004, then put in place a policy mandating intelligent design be included in ninth-grade biology classes.
On many days, Kitzmiller carpooled to Harrisburg with other plaintiffs, sitting on a wooden bench for hours and listening to testimony.
One day last month, she answered the phone at work and learned that the judge had issued a ruling that overwhelmingly favored the parents.
"He (the judge) actually saw," she said. "He heard and listened."
She hung up, then broke down.
These days, the Kitzmiller household is back to normal -- a new normal, a post-trial normal.
Sitting on a sofa in front of a fire, the woman who used to try to sleep through high school civics class explained that she now belongs to community groups and keeps an eye on her local government.
"I've never really been one to make waves," she said. "But now I'm involved, and I'm going to stay involved. If you do speak up, you can make a change."
The Kitzmiller name is now famous, like Roe, Wade and Scopes. It has been merchandised on collectible bears, T-shirts for dogs.
The case has been cited in another law complaint, a case in Fresno, Calif. It wasn't until Kitzmiller read that complaint that she realized her name is part of history. Law-school students recognize it. People from other states, possible plaintiffs in other suits, call her for advice.
Someday, Tammy Kitzmiller might get remarried and be Tammy Kitzmiller no longer.
And she's fine with that; this was never about being on the news.
"I've been trying to focus on (her daughters)," she said. "When the trial was over, I gave them both a big hug."
She felt bad about being away from them so much, dealing with the trial, going to work.
"That's the way I am. That made me feel bad," she said. "I love my kids very much and they're the world for me."
"I think that's my constant worry," she said. "Have I done right by them?"
"I hope I've set a good example."
Reach Christina Kauffman at 505-5434 or email@example.com.