A Japanese girl just graduated from junior high as a class of one, as the “light goes out” on a small town.

Tokyo — When Akino Imanaka attended her junior high school graduation earlier this month, the whole community turned out to celebrate. It wasn’t just that Imanaka had ranked at the top of her class — she was the class. Imanaka was the sole student on the island of Oteshima, a tiny speck of land in Japan’s famed Inland Sea.

“It was a little lonely, but really fun,” the 15-year-old told CBS News on the phone, recalling her experience as the only elementary school and then junior high student on Oteshima, about 10 miles north of the main island of Shikoku, in western Japan.

Tutoring the teen over the past few years was a team of no less than five instructors, each responsible for two subjects. Among them was Kazumasa Ii, 66, who taught Japanese language and social studies. Trying to create any semblance of normal class life prompted the staff to take on some unusual duties: Besides lesson plans and grading papers, they occasionally had to stand in as classmates.

“We expressed our opinions and offered opposing views” so their star pupil could experience class discussions, Ii told CBS News.

Like much of rural Japan, Oteshima faces almost-certain oblivion. When Ii moved to the island 30 years ago with his young family, his kids had plenty of playmates, all watched over by village elders. These days, stray cats — which greedily swarm the dock three times a day when the ferry arrives — vastly outnumber the several dozen permanent residents, most of whom earn a living by fishing for octopus and sand eels.

Tourists arrive each spring to gape at the bountiful pink and white peach blossoms blanketing Oteshima, but with neither stores nor hotels, even teachers at Oteshima Junior High have been compelled to bunk in a dorm, returning to the mainland on weekends for groceries.

Most of the islanders are senior citizens, and the average age of Oteshima’s tiny population is set to rise even more soon, as Imanaka leaves to attend a mainland high school where she’ll be one of 190 students.

Ii concedes that outsiders might reasonably question the utility of keeping an entire school and its staff on the clock for a single student.

“Of course it’s inefficient,” he said, speaking from Oteshima Junior High as it prepared to close its doors, likely for good. But rural schools, he argued, are much more than places of learning.

“A school gives its community vitality,” he said, noting that islanders would faithfully show up not just for graduations, but to join sports and other school events.

“When a community loses its last school,” he said, “it’s like the light goes out.”