North Dakota's public schools do not have authority to spend tax money on college scholarships for their graduates, Attorney General Wayne Stenehjem said.

Stenehjem's legal opinion, issued Thursday, came at the request of state Rep. Kenton Onstad, D-Parshall. The Parshall school district recently began offering scholarships of $500 per semester for graduates who went on to college and maintained a 2.5 grade-point average, Onstad said.

He asked for the opinion because of questions from some school parents who wondered whether the scholarships were legal, and were annoyed that another program was being shortchanged on school supplies, Onstad said.

"It would be a great idea if you could do it," Onstad said of the scholarships.

Onstad said the district has begun receiving income from oil production on its property, and some of it was being used for the scholarships.

Stenehjem, in his opinion, said North Dakota law does not authorize schools to "undertake activities, or to spend public money, for purposes other than kindergarten through 12th grade education."