The April issue of the newsletter for Frontier School District in Hamburg, N.Y., contains a coupon that will allow gun owners to get a discount on trigger locks.

The district has teamed with Wal-Mart, the nation’s largest retailer, for the program. The store usually sells the combination locks for $10.74. With the coupon, good only at the Hamburg Wal-Mart, the locks will be $6.

“Guys will go out and buy a $1,000 gun, but they won’t buy a $13 lock for it,” said Timothy Crino, a parent, district resident, and special agent with the FBI, who recommended the combination lock.

School officials could not estimate how many guns there are in the district. The Safe Kids Coalition chapter based at Children’s Hospital of Buffalo estimates as many as 50 percent of households in the country have firearms.