GRAND FORKS – The Mixed Voices Community Choir will present its first spring concert at 7 p.m. Tuesday, May 12, at Calvary Lutheran Church, 1405 S. Ninth St. A free will donation will be taken to support the Lewis and Clark Elementary School's Parent Teacher Organization. The concert, titled “Over the Rainbow: Songs of Hope, Healing and Happiness,” said Whitney Berry, the choir’s director. The Mixed Voices Community Choir will be joined by the L…