In my side mirror, I saw Ethan standing on the stone portico beside his mother and father, his hands still in his pockets, watching the red taillights head toward the valley.

Four months later, the folding metal chairs in the Colorado Springs Elementary auditorium scraped across the polished gym floor at two in the afternoon.

Lucas stood beside a long wooden table in the center aisle, unrolling a big poster board covered in hand-drawn force vectors and structural tension diagrams.

“Did the balsa wood stay level on the left side?” I asked.

“The joint cured for twenty-four hours,” Lucas said, scuffing the toe of his right shoe on the floor.