After sending out your resume it's important to follow up with employers. With many people still out of work due to the recession and thousands of students and seasoned workers in the market for internships, employers will take notice of applicants who contact them again and real show their interest in the company.
This follow up can be key in securing an internship for fall semester. Your motivation and initiative will be rewarded by the organization since most employers prefer interns who take the initiative to do what it takes to get an internship with the company. I often hear from students that they are just waiting to hear back from an employer and I always recommend that they take the initiative to follow-up on each application or resume they send. This strategy provides valuable information for students since they can find out when an employer plans on making a decision and if the student is still being considered for a position as an intern.