Stonington — If his mother had not registered him at the last minute for a children’s summer camp at Mystic Aquarium, Stonington High School senior Jay Christopher may never have found his calling.

And it has nothing do to with whales, dolphins or fish.

This coming September, Christopher will head to Darwin, Australia, for a 90-day, 7,800-mile training voyage aboard a two-masted schooner that will earn him not only college credits but also the opportunity to sit for the licensing exam to captain 200-ton yachts.

And while his post-high-school plans are very much different from those of his classmates, so was his high school experience, as he was enrolled in an internship program the past two years in which he mixed time in the classroom with performing maintenance such as sanding and varnishing the schooner Brilliant at Mystic Seaport Museum during his junior year and working for an oyster farming business in Noank this year.

“It’s hard work but good work. It’s a different kind of work on the water than I’ve ever done,” he said about the two jobs.

But back to his summer camp story.

When he was 8, his grandparents were unable to come up from Florida to take care of him during the summer while his parents, Cheryl and Jeff, were at work. So his mother enrolled him in the aquarium summer camp. What she didn’t know was that campers spent the mornings at the aquarium and the afternoons at the Seaport’s sailing center. Soon after, Christopher said, he ditched the aquarium part of the camp and spent all day at the sailing center.

He was hooked.

By the age of 10, he was sailing competitively with Thames Yacht Club, New England Science and Sailing and the Mudratz. He bought an Opti, or Optimist, a small single-handed sailing dinghy.

Since he was 16, he has been the lead instructor for the Seaport’s community youth sailing program. Most days in the spring, summer and fall, he can be found at the sailing center teaching.

“I’ll sail anything,” he said.

As for how he approached his post-graduation plans, Christopher admitted, ”I’m not really the best student in school.”

So in his junior year, he said, he and his parents began looking at what he could do after graduation as an alternative to traditional college. He said his father found Sea/mester, a Florida-based organization that mixed sail training, leadership and ocean science.

On Sept. 15, Christopher is slated to leave Darwin, Australia, aboard a 112-foot schooner with stops at Komodo Island, Bali, Christmas Island, Cocos (Keeling) Islands and Mauritius, arriving in Capetown, South Africa, on Dec. 15. During the 90-day, 7,800-nautical-mile voyage across the southern Indian Ocean, he will stand watches, learn the operation of the boat from navigation to cooking and take 12 credits of classroom instruction in nautical science, marine biology, leadership and oceanography.

Completion will allow him to sit for the 200-ton master’s yachting certification exam. After that he plans to begin working on yachts.

As for his fascination with sailing small boats to large yachts, Christopher said, “It’s just free. I can’t think of a better word.”

Stonington High School business teacher William Yuhas, who oversees the growing internship program, called Christopher an extremely motivated student.

“He’s not someone you have to light a fire under to get them moving. He knows what he wants to do,” he said.

Yuhas pointed out that Christopher’s internships required a lot of hard, manual work, and with the smell of the shellfish operation, he joked, “you have to be motivated.”

“He’s mature. He knows what he wants to do and he takes it seriously,” Yuhas said. “It’s rewarding to see the passion he has for this.”

j.wojtas@theday.com