DANVERS -- Xaverian Brother Timothy Paul, the ninth-grade biology teacher at St. John's Prep in Danvers, has the remarkable ability to say words like "cytoplasm" and "mitochondria" with a gentle, fatherly air. On the afternoon of Dec. 12, when The Pilot visited St. John's, Brother Tim was hunched over with hypnotic zeal during his lecture.

"So the magic number there is going to be eight, right?" Brother Tim asked his students, whom he calls "gentlemen." "Well, I have some bad news for you. You see, glycolysis, all this stuff, glucose, all the way to pyruvic acid. That takes place in the cytoplasm of the cell."

He drummed his hand along the whiteboard as he taught, his shadow dramatically looming over the complex chemical diagram he had drawn.

"How are those guys ... gonna get into the matrix of the mitochondria?" he asked. "That's the question. And you know what? It's tricky."

Speaking to The Pilot after class, Brother Tim, who has taught at St. John's Prep for over 50 years, said that he wants his enthusiasm to be contagious. An intimate, energetic style of teaching comes naturally to him. He knows that most of the boys he teaches will never have another biology class in their lives.

"My job is going to be to try to give them some really basic stuff about how living things work in our world, so that when they leave here, they'll probably remember some of it," he said.

Fittingly for a biology teacher, Brother Tim is himself something of an endangered species. He is the last Xaverian Brother to be teaching at St. John's Prep, a school of 1,500 boys in grades six through 12. The school was founded by the Xaverian Brothers in 1907. Brother Tim is the only remaining link to that heritage. One by one, he has seen his fellow brothers retire from teaching. All of the brothers he lives with have at least one master's degree. Some have doctorates. He is saddened that their knowledge is no longer present in the classroom.

"I think that we have been very lucky in our training as brothers, both as religious and in our training academically," he said.

In celebration of his half-century of teaching and mentorship, Brother Tim was inducted into the St. John's Prep Hall of Honor in 2024.

"It's such a great benefit to our students to have Brother Tim," Jim Frackleton, assistant head of school for marketing and communications, told The Pilot. "Such an amazing experience over his 50-plus years of teaching. He's highly educated (and) loves engaging with students."

Frackleton added: "He's just so approachable and humble. He really exemplifies the Xaverian spiritual value of humility."

After class on Dec. 12, Brother Tim had a meeting of the school Aviation Club, which he leads. After that, he had a swim meet. Brother Tim doesn't swim, but he's "a really good timer," if he does say so himself.

"My swimming days are over," he joked.

A St. John's Prep student started the Aviation Club in 2002, when Brother Tim was the school's principal. The student who founded the club is now a commercial airline pilot.

"I was always interested in aviation, but we have a vow of poverty," Brother Tim said. "I never had the wherewithal to be able to do it."

A generous alum paid for Brother Tim to get a pilot's license at Beverly Regional Airport in 2009.

"You don't know what that feels like," he said about flying for the first time. "It's amazing."

At first, he flew with an instructor who told him what to do. It was as simple as listening to the directions.

"But once you get to the stage where you can solo the airplane by yourself, that's when you start to think, 'Oh my God, do you realize what you just accomplished?'" he said. "You're able to take this airplane, bring it up into the air all by yourself, and bring it back down, and be able to do it again all by yourself. That's an amazing feeling."

The same alum who paid for Brother Tim's training has done the same for St. John's Prep students. Brother Tim himself is a certified ground instructor who teaches flight students at the airport. Over a dozen Aviation Club students have gone on to receive pilot certificates. Some of them are now flying for the Navy, the Air Force, and major airlines.

"They've actually gone on from that first experience they had, and they went and got their air transport pilot certificate so they can fly the big boys," Brother Tim said.

He always enjoys hearing from his former students. He recently received an email from an Aviation Club member who is now a pilot and instructor himself. He said that none of that would've been possible without Brother Tim.

"I think for a teacher, when a student comes back to you and says that you were the one, or one of the ones, that was a big influence in their life and what they did, that's the most satisfactory thing you can know," he said.

Since he was a child in Maine with a toy microscope, Brother Tim was fascinated with living things and how they worked. Much of the science he teaches did not exist when he was a high schooler at St. John the Baptist in Bangor, run by the Xaverian Brothers.

"I got to know them," Brother Tim said. "I got to be impressed by their way of life, with their teaching ability. I had marvelous teachers when I was in high school from the brothers, and that's when I knew I probably wanted to teach."

He told his parents he wanted to be a Xaverian Brother, and they gave him their blessing. He officially joined the order in 1966 and studied in Newton, then Silver Spring, Maryland. He took classes at the Catholic University of America, then returned to New England to study at Boston University. He briefly taught at Xaverian Brothers High School in Westwood before coming to St. John's Prep.

"The school is a wonderful school," he said. "The teachers that we have here are excellent. They really are, and it's always been a welcoming environment for everything. And that's the kind of thing that makes you want to come to school every day."

When he walks into the classroom each day, Brother Tim doesn't have an agenda set in his mind.

"My approach is always going to be, I'm going to have some sort of conversation where I ask questions, and I get answers. And the conversations get animated."

He has found that compared to past generations, today's students crave instant gratification. They want to know the answers, and if they don't know them, they want Brother Tim to tell them immediately. He suspects that social media has made them accustomed to everything being at their fingertips at all times.

"And I resist that because I say my job is not to just give you all of these answers," he said, "My job is to make you think. That's what I want to do. I want you to think out the answer to a problem you see rather than just be given the answers."

He is constantly asked when he plans to retire, and his response is always the same: He will retire either when he is no longer physically or mentally capable of teaching, or when he no longer enjoys it.

But, he said, "I don't think the time is going to come when I don't like teaching."