Races are shaping up for a selectman seat and treasurer-tax collector in the April 27 election. Incumbent Selectman Richard Ward will face a challenge for the three-year post from Paul Johnson, a member of the North Carver Water District Commission. Incumbent treasurer-tax collector John Franey will be opposed by Paula Nute, the assistant collector. Openings in other positions drew only single candidates, though voters can write in their choices. Two School Committee seats are open, and Gina Hanlon-Cavicchi and Barry Struski will be on the ballot. Current members Kevin Walsh and Cally Minahan chose not to run for reelection. Lynn Doyle, the town’s records technician, will be on the ballot for town clerk; the incumbent, Jean McGillicuddy, chose not to run.