A father and son walk uptown after joining crowds to celebrate the New York Giants' Super Bowl victory.

City students were among the hundreds of thousands of New York Giants fans who flooded the streets around City Hall today to celebrate the team’s Super Bowl victory.

I took a lunchtime walk near our Lafayette Street office to soak in the spectacle and encountered, amid the crowds, families who had pulled their children from school today for the ticker-tape parade along Broadway’s Canyon of Heroes.

It’s a practice that is not officially sanctioned but got encouragement from former Mayor Rudy Giuliani in 2000, when he said students should be allowed to skip school for the Yankees’ World Series parade, as long as they read a book about baseball as well. After the Yankees’ 1998 World Series victory, high school attendance was 72 percent on the day of the parade, down from about 85 percent on typical days.

The Giants have been less of a draw in the past. In 2008, the last time the Giants won the Super Bowl, school attendance fell by about 4 percentage points on parade day across all grade levels.

About 20 seniors from Queens’ Bayside High School had gathered at the corner of Howard and Lafayette streets after the festivities.

“We were very excited. We didn’t go to school,” said one student who declined to give her name because she had skipped school. “The teachers know we’re here, but no, none came with us.”

Outside Roll and Go Pizza at the corner of Broadway and Franklin Street, I met five students from Franklin Delano Roosevelt High School who said they had traveled from Brooklyn in a group of 20 but had lost their classmates in the crowds.

Senior Rifat Ahmed said she was too young to help celebrate the Giants’ 2008 win but had skipped school to celebrate the Yankees’ 2009 World Series victory. She said she went to FDR for two periods this morning — for a free period and gym class — before boarding the subway to Manhattan. (Another student said he hadn’t attended school at all today.)

“I just wanted the feeling of being there, with the toilet paper being thrown, and the footballs,” Ahmed said.

FDR is the school GothamSchools featured today in a story about teachers’ efforts to help an 18-year-old enrollee overcome illiteracy. It is also facing “turnaround,” or a process in which it would close and reopen with a new name and half of teachers replaced.

Ahmed said the city’s turnaround plan was misguided for FDR, which she noted serves many students who are considered English language learners and also routinely sends students to selective colleges with full scholarships.

“Our school has the greatest staff ever,” said Ahmed, a former executive in FDR’s student council. “Mayor Bloomberg — he’s not getting to know anything that’s happening there.”

Five students from Franklin Delano Roosevelt High School who attended the parade. Senior Rifat Ahmed is at center.