Most of America watched the twin towers of the World Trade Center collapse on their television screens as anchors warned that the shaky footage was not a made-for-television movie.

McCormick junior Gnyan Patel was sitting in his high school calculus class on Sept. 11, 2001, when he heard what sounded like “a sonic boom,” he said. His school, Stuyvesant High School, was only four blocks away from the site of the World Trade Center.

“A little while later, the principal came on (the announcement system) and said a plane had crashed into the World Trade Center,” Patel said.

At first, he thought the plane that hit the towers probably was “one of those small planes that fly on the water” and not a commercial airliner.

Uncertainty and rumors abounded after the second tower was hit at 9:03 a.m. The principal came on the announcement system again and said the Secret Service and FBI were not allowing anyone out of the school. Students tried to call their parents, many of whom worked in the towers, but that morning all the phone lines “were deadlocked,” Patel said.

The class schedule continued as normal, he said, but during the break between classes he passed by a row of windows facing the the World Trade Center. The twin towers were on fire.

“These flames were just huge,” Patel said.

In his next class students and teachers ignored classwork, traded rumors and watched television. Then the lights went out. The first tower had collapsed. The building shook.

“It was like a little earthquake,” he said.

As lower Manhattan was evacuated, Wall Street bankers and construction workers alike poured through Stuyvesant’s ground floor, mixing with students in their flight northward.

“A bunch of people just started running in screaming,” Patel said. “I was hearing this crazy loud sound… I’d known the first tower collapsed, but I didn’t know the second tower had collapsed. I just knew something crazy was going on.”

Then came the scariest moment of Patel’s day, frightening because it showed the intensity of the shock everyone was feeling. In the middle of all the people streaming into the school, Patel saw a “big construction worker” with a shirt wrapped around his face standing in Stuyvesant and crying.

“He was crying and he looked like he was about to throw up,” Patel said. “One of the teachers near me was like, ‘Are you OK?’ He was blubbering about how he’d seen people jumping out (of the towers).”

As students and fellow Manhattanites walked out of the school and headed north, Patel said, they were followed by slowly spreading dust clouds from the debris of the towers. He and his friends stopped to eat in a pizzeria, but it was completely silent with all its customers watching a television showing footage of Ground Zero, he said.

“Eating in there was the most depressing thing ever,” Patel said. “I’ve never seen Manhattan that quiet.”

But some things don’t change in Manhattan. Initially, the subway system was shut down due to security concerns, and Patel worried about having to walk the length of his 1.5-hour commute, he said. In a few hours, though, the trains started running again.

After Sept. 11, Stuyvesant was used as a triage center for Ground Zero so students attended night classes at Brooklyn Tech. The school did not reopen until Oct 10. The first few weeks back were strange, Patel said. Downtown Manhattan was mostly empty, other than the National Guardsmen with machine guns, guard dogs and Hummers, he said.

“It was just kind of weird, seeing that on your way to school,” he said.

After the World Trade Center collapsed, he realized how much of New York he’d taken for granted and began exploring neighborhoods and sightseeing more than he had before. He also purchased a display of the New York Skyline — with the Twin Towers intact. The foot-long display now sits on his dresser at school.

“Every morning I used to come out of the train station, and the sun was shining on them, and I’d be like, man, that’s the most beautiful thing in the world,” Patel said. “I don’t think I ever realized that could ever happen.”

Reach Tina Peng at [email protected].