Traffic violations aren't a special "class" of offence - they can be misdemeanors or felonies just like any other crime. For example, a DUI is a traffic/moving violation just like speeding is, but they're not necessarily both the same "class" (DUIs are almost certainly felonies).
You need to look at your state and city laws. Some states consider speeding offences and other moving violations to be misdemeanors (in which case you absolutely must report them and not doing so could easily get your acceptance rescinded), while others consider them to be "infractions" (which are a lower level of crime below misdemeanors, which you may or may not need to report depending on the school).
No one here is a lawyer (presumably) and no one here can ethically advise you on whether your specific situation is considered a misdemeanor/felony. If you're worried about this, you need to talk to an actual lawyer and figure out what offences you've committed and what levels they were considered at.