You start off with a nice credit score so that you have enough room to go down over time. If you pay your bills on time, your credit stays high, and if you miss payments or are carelessly paying stuff on credit, it will go down.

Avoid using credit cards, and if you do, make sure that you pay your credit cards on your next paycheck. If you don't, your credit score will go down, and your bill will drown you.

My best guess as of why you guys started off with a higher score than usual is because none of your parents have a SSN registered to their credit. Your initial credit is based on your parents, so if your parents are heavily in debt, the credit companies assume that you will also be in debt, so they give you a lower score. If they have nobody to compare you to, they have high expectations from you.

Some of you guys are probably new to credit scores and maybe even credit cards. Don't become irresponsible and get in debt. On;y buy things you can afford to pay within the next month (Not including car and House).