Bring a large pot of water to a boil. Toss in the pasta and cook according to the directions on the box. Meanwhile, pour the vinegar into a large bowl. Slowly whisk in the oil. Season with salt and pepper. Add the corn, tomatoes, scallion, and arugula. Toss until coated. When pasta is done cooking, drain the pasta and then toss with the dressing. The arugula should begin to wilt. Season with salt and pepper and sprinkle on a little parmesan.