Those of you, the DREAMers (meaning you came to the country as minors) may not even be aware what your parents did and thankfully, while there is a provision to forgive you if you or they made a false claim to US citizenship prior to your 18th birthday, your story should still hold together to prove that you meet all requirements.
If you are one of those individuals who used the passport and visa of another person to enter the US legally, used another name(s) while here, or assumed the identity of an American citizen, have documents that are in several different names, or some other situation in which you have used multiple names and identities, you have to sort it all out to see if you are even eligible. As an example, if you entered using a passport that does not belong to you, but you went to school or worked or rented apartments under your real name, you will not be able to prove anything because your information will not match with that in the US Government records. It is also not clear if the USCIS will insist on looking at original birth certificates before approval and if that is the case, it could get messy. In all instance of forged and/or fraudulent documents and multiple identities, it is best to consult with an attorney.