Heat the oven to 375°. Trim off and discard the ends of each zucchini, then halve them lengthwise. Trim a thin slice from the curved side of each portion so that it sits flat. Scoop out and discard the center flesh of each zucchini to form a canoe.
In a medium bowl, stir the ground turkey, corn, onion, egg, garlic, chili powder, and salt together until well blended. Evenly distribute the mixture among the zucchini halves, packing it in and mounding it slightly.
Arrange the canoes on a baking sheet. Bake for 40 minutes. Serve with salsa, cheese, or your family's favorite chili toppings.