AIG Investments Group offers a 10-week internship in which you are assigned a specific group team based on the internship managers' judgment of fit. Once you are assigned a team, you are then assigned a direct boss, who is a more senior-level manager, and a mentor, who is relatively more junior. They both act as your guides throughout the 10-week program, with your direct boss being more of the one to give you assignments, and the mentor as someone who you can ask quick questions to. Throughout the 10-week program, you'll have opportunities to sit down with both your boss and mentor and discuss your goals and what you want to make out of your summer experience.
Yes. Each one of us was assigned a manager. We usually had a one on one session with our manager each week. The helpfulness comes in two ways: first, one could get a timely feedback on work/projects one was assigned; second, one can ask career related questions during the one on one session, which had less fluff.