Most schools that "celebrate" Spring Break don't begin until the second week of March. So overall there shouldn't be much in the way of crowds during that first week of March.
Big question marks on the weather. We're at the mercy of cold fronts throughout the winter and March is the same way. Most days should be sunny and temps in the 80's. However a cold front will bring (usually) one day of clouds and rain unless the thing stalls on top of us! A passing front brings cooler weather behind it but clear skies and bright sunshine. We had a front pass this weekend that brought us a freeze warning yesterday and only mid-50's today with lots of sun, but we'll have mid-60's Monday, mid-70's Tuesday and close to 80-degrees by Wednesday. March will be warmer than this with fewer cold front activity.
BobK/Orlando