Eric Potter helps bring materials to the roof of Crossett Brook Middle School in Duxbury, where teacher Melissa Williams’ grade five-six class installed a nighthawk's nest last week. Bud Towndrow, who works at the school, built the nest. The students worked with Larry Clarfeld from North Branch Nature Center. Nighthawks have stopped nesting in central Vermont; this is one of two nests developed this year to attract the birds. The other is at U-32 in East Montpelier.