Undecided Major?

<p>I applied undecided to my top two schools because I want to do Mechanical Engineering and it is much harder to get into for engineering (I would have NO chance of getting in if I put Engineering). So if I get in I will be taking regular classes not any for a specific major, is there anyway to get back on track with the other kids or will I have to go for an extra semester? Could I go to a local school over the summer just to take the classes?</p>