In the 1980s and 1990s, when the country’s university entrance exam industry was at its peak, cram school veteran teacher Toshiyuki Sakai would regularly stand in front of a classroom overflowing with students.

“When opening the classroom door, I could feel the heated atmosphere among the students pulsing through the room,” said Sakai, 60, who has taught contemporary Japanese writing at Tokyo’s Yoyogi Seminar cram school for 32 years.

Amid severe competition for top universities, many parents would send their children to yobiko (cram schools), which provide services for high school students and graduates prepping for university entrance exams.

Sakai said he would teach a 90-minute evening class from Monday to Friday every week in a classroom accommodating as many as 500 people, with some 600 students packed in.

It was so crowded that many students had to stand, with some of them using binoculars to read the blackboard, he said.

“After every lesson, about 50 students would wait in a line to ask me questions, and sometimes even to seek advice about life. It was always past 11 p.m. when I could finally get out of the classroom,” Sakai said.

Now, his lessons have a maximum of 50 attendees, reflecting the significant decline in the number of students in the country, a phenomenon that can be put down to the country’s dwindling childbirth rate.

“It’s not only the number of students that has changed,” Sakai said. “Students have become quieter and less active. It’s a little sad.”

In the spring of 1964, 15.5 percent of Japanese high school students entered university. The figure later took an upturn in line with increasing childbirths and the country’s rapid economic growth.

Against that backdrop, Yoyogi Seminar, founded in 1957, expanded its business across Japan from the late 1970s to early 1990s, with its main rivals Kawaijuku and Sundai cram schools also taking the opportunity to expand amid fierce competition in the sector.

Yoyogi Seminar had a total of 27 campuses and more than 70,000 students at its peak.

The number of applicants for universities and colleges peaked in Japan at approximately 1.21 million in 1992, the year when second-generation baby boomers turned 18 years old.

At the time, with large numbers of students competing for limited university places, there were an estimated 300,000 high school graduates who failed their entrance exams and were preparing to try again the following year.

At one stage, Yoyogi Seminar was erecting school buildings just outside big city train stations from which teachers would instruct in large lecture halls.

Such a business model, however, could not sustain itself as student numbers fell.

In the winter of 1989, Yoyogi Seminar began providing lessons by satellite, which enabled students to watch a live broadcast of classes given in Tokyo. The school later launched a system to make lessons available via the internet.

Currently, Yoyogi Seminar provides video lessons for more than 800 high schools across Japan and cooperates with some 400 cram schools in a similar way.

Hosho High School in Miyazaki Prefecture introduced Yoyogi Seminar’s video lessons in the 1990s for its students in the absence of a major cram school in the area.

The high school says it wants the students to take “the highest-level lessons” in the program.

After becoming such a well-known brand, Yoyogi Seminar shocked the nation in 2014 when it announced a plan to close the majority of its university entrance schools.

Some of the closed school buildings, located in prime locations near major stations, have been turned into hotels and apartments.

“Cram schools had no choice but to change in line with the times,” said Toshiro Takamiya, Yoyogi Seminar’s vice director.

While the number of students applying for universities has fallen, Yoyogi Seminar has seized an opportunity presented by the number of children taking exams for middle schools, particularly in urban areas.

Children can enter local public junior high schools without taking entrance exams. But parents seeking a better education for their children turn to middle schools combining junior high and high schools and requiring entry tests.

In May 2010, Yoyogi Seminar purchased a cram school aimed at sending students to top junior high schools.

It has expanded its group cram school Y-SAPIX across Japan, partially targeting younger students with the aim to provide consistent service from elementary school through to university entrance exams.