Studies show unequivocally that the longer your stay, the more personal, academic, and professional benefits you will reap from the experience. An academic year or a semester abroad allow the kind of cultural immersion that have the deepest impact in terms of personal growth, academic value, and career preparation. However, if timing or financial issues prevent a longer study abroad period, then a shorter-term program is certainly better than not participating at all. Summer programs exist in varied lengths and will not interfere with the schedule of the traditional academic year.
Make sure you explore all of your options, however, before you rule out a semester or year abroad. Financial aid may be available, and you may find that you can take courses while abroad that will help you make academic progress toward your degree.