It's never too late to start an exercise routine and diet. Whether or not it'll make a difference depends on how much time is left before spring break and how much of an improvement needs to be made.
Since you've waited until very close to spring break to get started on a routine, you can rule out making a drastic difference in the way you look. The amount of time needed
to make an improvement is different for all people.
Some people lose weight quickly and others have a hard time. The absolute minimum amount of time you'll need is about a month. Its safe to lose up to 2 pounds per week, so in a month, you can shed 8 pounds.
In most cases, 8 pounds is a sizeable difference. So the answer is yes, even last minute changes you make to increase your exercise and lower your calorie intake can help you achieve, if not a perfect, a better spring break body.