Preheat the oven to 400°F and line a large sheet pan with parchment paper.
In a mixing bowl, combine the ground turkey, breadcrumbs, egg, minced garlic, oregano, salt, and pepper. Mix until just combined, then roll the mixture into 16 meatballs and place them on one side of the sheet pan.
In the same bowl, toss the zucchini slices, cherry tomatoes, and olives with the olive oil. Spread the vegetables around the meatballs on the sheet pan in a single layer.
Bake for 20 to 25 minutes until the meatballs reach an internal temperature of 165°F and the vegetables are softened and lightly browned.
Remove the pan from the oven and sprinkle the chopped parsley over the top before serving.