1. Preheat oven to 375ºF. Line a baking sheet with foil. Arrange chicken nuggets on baking sheet and sprinkle with chili powder. Bake until crispy and cooked through, about 25 minutes.
2. Combine avocado and lime juice in a small bowl. Warm oil in a large skillet over medium heat. Add scallions and bell pepper and cook, stirring, until softened, about 3 minutes. Add corn and sauté until warmed through, 5 to 7 minutes. Remove from heat, stir in cilantro and season with salt.
3. Divide corn mixture among tortillas, top each with 2 or 3 chicken nuggets and some avocado mixture. Fold over and serve.