School officials made the announcement at Thursday's school board meeting, closing the meeting in his honor.
"He definitely did touch the lives of many and our thoughts are with his family at this time," board president Elvia Rivas said.
Kidwell, who served as deputy superintendent for the district, retired in 2010.
He worked at OMSD for more than 12 years.
Superintendent James Hammond described Kidwell as "a remarkable man."
Hammond said Kidwell was the one administrator, when he first arrived in the district, who truly passed the baton to him.
"He didn't have to do this but on occasion, he would get an email or an phone call, and he just wants to check in and say hello," he said.
Hammond said he has received several phone calls and emails about Kidwell's legacy in the district.
"I was very saddened by his passing and he will be missed," Hammond said. "His legacy will live on with his family, students and staff that he impacted."
Services for Kidwell have not been announced.
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