PATERSON , NJ – First-graders at School No. 21 in the 4th Ward found something in a neighborhood backyard last week that seemed interesting to them. So they brought it to school. One of them even brought some home.

What they found were $10 packets of heroin, officials said.

Sign Up for E-News

“It’s obviously a concern,’’ said Paterson Schools Commissioner Jonathan Hodges. “What concerns me is if they didn’t know what they had, what if they had sampled it? What if it was cut with sugar and they sampled a lot of it? This could have been very bad.’’

The case seems emblematic of the challenges confronting parents and educators in some of Paterson’s toughest neighborhoods.

There’s no indication the children knew they were carrying a potent narcotic, officials said. Their parents were given the choice whether to have the first-graders tested in case any of them ingested the heroin, and those who were tested had their results come back negative, officials said.

Officials said they learned of the situation Wednesday morning when one the children’s parents contacted a teacher and said the child had come home from school with a packet that seemed to contain drugs.

“The teacher contacted the principal and substance abuse coordinator in the school and they were able to find out there were several packets still in the school after talking to the 1st graders,’’ said Security Director James Smith in a statement issued by Paterson Public Schools. “The affected parents of the class were notified after several packets were retrieved in the school. It was learned that some of the students had found these packets in a backyard and brought it to school.’’

Paterson police later tested the contents of the packets and confirmed they contained heroin, officials said.

“The parents thanked school officials and talked to police with the children about the circumstances on how they came into contact with the packets,” said Smith’s statement.

Officials did not release the location of the backyard where the children found the drugs. Authorities said the first-graders could have happened upon someone’s hiding spot, or the heroin may have been accidently dropped there.