DICKINSON - Marie Makaruk is almost 80 years old and walks with a cane, but inmates and staff at the Southwest Multi-County Correction Center say she is among the toughest at the lockup.

Makaruk, or "Mrs. Mak," as she's known to students, is retiring Friday, after 10 years of teaching at the correctional center. She began teaching in a one-room schoolhouse in 1944, in a North Dakota town that no longer exists.

Her small classroom in Dickinson is built of concrete with stainless steel desks and some posters on the walls. The students - all juveniles - are taught the three R's, along with lessons in literature, history, geography and on the constitution. They sit quietly as Makaruk works with them as a group, or one at a time.

Makaruk asks only that they take their studies seriously.

"It's rewarding to me to see their eyes sparkle when they realize they have discovered something," she said.

The Dickinson jail houses male and female adult prisoners from North Dakota. It also is a federal juvenile facility for boys from throughout the United States. The young prisoners are convicted of crimes ranging from illegal drug use to murder.

Makaruk refers to them as children. And the great-grandmother sometimes bakes them cookies.

"I would rather not know what they've done," she said. "I'm a teacher - I'm not here to judge them."

Student inmates who have drug convictions typically have a head start on the metric system, she has found.

"They know kilos and grams, but ordinary math - forget it," she said. "There's a little paradox there. Sometimes I don't know whether to laugh or cry."

She won't waste her time on a student who doesn't want to learn.

"If they horse around, they're out," she said.

"She has a gentle, unthreatening manner," said Ione Sickler, who oversees juvenile programs at the correctional center. "She also instills in them what's acceptable and what's not acceptable. She makes them toe the line - and there are some tough kids here."

Derek, a 16-year-old inmate from White Shield, said he learned quickly that Mrs. Mak is not one for nonsense.

"I used to give her trouble, then I started listening to her," the teen said. He's glad he did.

"I was dumb when I got here," he said. "I'm kind of smart now."

Derek has been one of Makaruk's students for about 18 months. His strong arms strain from the bundle of textbooks that he takes back to his cell to study for his high school diploma.

Makaruk said her "kind-but-firm" teaching philosophy won him over.

Derek now fetches a chair at the beginning of class for his teacher, who must sit down during lessons. She turns 80 in June.

She is in the classroom five days a week, for about three hours a day. Class sizes range from one to about a dozen students.

Makaruk was 18 when she took her first teaching job in Fayette, a now-abandoned Dunn County town. She passed an "emergency teaching exam" given during World War II because of a shortage of teachers. She then earned a two-year teaching diploma, and later an education degree from Dickinson State University.

She taught at rural schools in Billings and Stark counties, and at the school district at South Heart for 17 years. Between teaching stints, she raised four children. She's been a widow for seven years.

Three of her former students are employed at the Dickinson facility.

Rita Binstock, the office supervisor, said Makaruk was her 5th grade teacher in South Heart some 30 years ago.

"I'm not going to lie - she was strict. She wanted you to learn and that's how it was," Binstock said. "She stood out and made an impression on me, most definitely. She taught us our learning capabilities and she taught us respect."

Binstock believes Makaruk is perfect for the teaching job.

"She's still strict," Binstock said. "If those kids don't listen to her, she sends them back to their cells."

Makaruk was 70 years old and retired from teaching when she answered a newspaper ad a decade ago seeking a teacher at the youth correctional center.

"The only thing I know is how to teach," she said.

Most of her prison students are more "academically challenged" than their counterparts on the outside, she said, and many of the inmates have not had parents who put an emphasis on education.

Still, she said, her job there was probably the most rewarding of all her teaching jobs.

"I think these students are the most needy," she said.

"My instinct is telling me it's time," Makaruk said of her upcoming retirement. "I've enjoyed a long, rewarding career. I'll miss it."

After she retires, she hopes to write a story of her childhood and of her Ukrainian ancestors to share with her family. She also wants to learn how to use her new computer and how to send e-mail.

And she will be thinking about her students still in prison.

"All I can hope," she said, "is that when they leave here they will have learned that education is important."