I really did enjoy the movie, I wouldn't necessarily say it would be in my top tier of movies.
However, it definitely did touch on some themes that are very indicative of coming of age, generational divides and how aiming for one thing can lead to the exact thing you don't want.
SPOILERS:
Dustin doesn't know what he wants in life and the pressure to succeed frightens him.
With his lack of understanding and need to please and live up to others expectations he abandons himself on a daily basis.
Mrs Robinson sees that, as well as an attractive man and figures it's a great way to get a distraction from her life.
You can see her manipulating him and his naivete allows her to do so.
Even her husband shares with him he is unhappy with his life and rushed he had been more free and relaxed in his younger years.
However, as a paradox, it's this exact thing that starts to give him a sense of purpose and doing things he wants to do rather than aimlessly being pushed around by others around, albeit even if well meaning.
Elaine is a prime example of him finally pursuing his desires.
Elaine also is under societal pressure.
University feels like a blip of what is expected in get life, which is to marry the first 'decent' man that comes along.
Both young adults feel pressured and so follow their passion, alienating those close to them as a result.
A divide between the previous and future generations... But the question is, did the new generation repeat the previous generation's mistakes, just in a different way?