The actress, who is now gaining rave reviews for her role in The Help, has never met her benefactor, who set up the scholarship as a Julliard alumni.
She tells WENN, "It paid for my schooling, back and forth to go home for Christmas, books, everything. He actually made it possible for me to go to school there because my family were not incredibly wealthy and I was the first one to go to college.
"He's a very generous alumni and the board at Julliard give it (scholarship) to a student every two years and I received it so I was very lucky."
She almost met Williams at a restaurant - but he dashed out before she got the chance to say thank you.
She recalls, "I was telling someone at a restaurant the story about my scholarship and Robin Williams comes in and sits down at a table next to me! I said, 'OK, I'm gonna wait until he's done eating,' because he was with friends. But, before the waiter even cleared his plate away, he jumped up and ran out like he was running late.
"I had the urge to go run after him but I thought he would think I was crazy. I missed the opportunity to thank him for his generosity, so I'm sure at some point I'll be able to meet him at a party or an event and I will then be the crazy person who runs up to him and says, 'Oh my gosh, you changed my life!'"