I agree with the others who suggested that you contact your schools and see where you can improve. You may be surprised by the feedback you get--make sure you use it.
Did you have a chance to read the references? Did you have an academic reference in the mix? That is, not just someone who is a teacher but someone who can directly comment on your academic ability? I would just make sure that all of your letters are strong and that the people writing them are familiar with an MSW program. You want to make sure that they hit all of the key words to describe your skills and abilities so that they
