To the first graders at P.S. 163: Please add an item to your homework assignments for the very last day of school in your final year there, when you’re in fifth grade. Write a thank-you note to Joey’s mom, Allison Downing.

By the time you’re 10, Mrs. Downing – the lady with the curly blonde hair and big smile – will have raised hundreds of thousands of dollars for things that benefit the school such as chess instruction, a brand-new skeleton in the science lab, and new library books.

This year alone, Mrs. Downing, who used to work for a congresswoman in Washington, D.C., has helped bring in $100,000.

How does she do it? Mrs. Downing is the president of Friends of P.S. 163, and she has help from many parents and friends. Remarkably, the group only started last year at the school on 97th Street and Amsterdam Avenue, known for its bilingual instruction and diverse population. And it comes at just the right time, as shifting demographics are putting a strain on public funding. Case in point: the school is on the threshold of losing its Title I funding, which provides free lunches.

So now you have a bit of an explanation of what your parents were up to on Friday night, when they left you at home with grandparents and babysitters. The first grade parents got together to help raise money for the school.

The event took place at the home of Julian’s parents, Yvette Leeper-Bueno and Adrian Bueno. Lots of famous people were there, such as the school principal, Virginia Pepe; the co-president of the P.T.A., Moira Dolan; the president of Manhattan, Scott Stringer; the past president, C. Virginia Fields, and the neighborhood’s state assemblyman, Daniel O’Donnell, who was late because there was a fire on his block and he had to make sure everyone was safe.

A highlight of the evening was the contest for the best-tasting guacamole. Carrie Reynolds, mother of Anna, had the winning entry. Although the parents have different kinds of jobs and come from different places, they clearly enjoyed each other’s company.

Some parents had assignments at the party. Mrs. Downing stayed at the door to greet guests. Jessica Weigmann, Warren’s mother, sold raffle tickets. She was glad the $4,300 raised was earmarked for the chess program, because Warren loves chess.

“It’s his favorite thing. Even if he’s sick he wants to come into school for chess,” Mrs. Weigmann said.

Not all first-graders like chess as much as Warren, according to their parents, anyway. Take Sylar Bromley, who is more interested in academics than the Royal Game. “She’s more scholastic; she likes to do all her homework for the week on Monday night,” Skylar’s mother, Kyra Bromley, said.

But in the end, the event wasn’t about chess. The first-grade parents were just happy to come together to help P.S. 163.

“It sprung out of nothing,” Mrs. Bromley, a lawyer, said. She did the legal work to incorporate the group as a nonprofit 501c3 last year.

“For whatever reason and no particular reason, last year’s kindergarten parents were motivated and wanted to spend the time and energy,” Mrs. Bromley said.

Mrs. Downing has her own explanation for the group’s rapid success: She likes the school and the children. “The kids in Joey’s class are exceptional. Each one is a completely wonderful person,” she said.

So here’s another assignment, for right now up until that last day of fifth grade: Keep on being exceptional and Mrs. Downing and other parents will keep raising money for your school.

It may just make city officials give more money, too. As the Manhattan president, Mr. Stringer, said at the party: “We want to come back and do even more for the school.”

agordon@nysun.com