The Harry Potter actress, 23, is due to leave Brown University in May after having extended her graduation date by a year.
Donning a pretty pink crop top and tight black skirt, Emma excitedly opened her amusing present from Ellen and fellow co-host Jason Bateman.
"Jason bought it," said the comedian, handing Emma a brown paper bag. The English beauty pulled out a bright blue silk graduation hat, with the phrase "I ♥ Ellen" emblazoned across it.
"Thank you," laughed Emma as she tried it on. "This will be good for the real thing."
"And you won't stand out that's the great thing," said Ellen.
The child star also spoke about her university experience during the interview on The Ellen DeGeneres Show.
"I guess everyone in their freshman year is nervous and figuring it all out," said Emma. "I think people kind of took pity on me. She's English, she doesn't really know where she's going. And Brown were weirdly protective of me. They saw it as their role to help me have that experience. I can't really explain it."
The Noah actress added that with her extended graduation date, her dad liked to make fun of her.
"So in America you guys graduate in four years and I graduate in five," said Emma. "I took two whole semesters off and then I worked during all of my breaks.
"My parents can't really get their heads around it. In England we graduate in three years and my dad's like, 'When is this happening? When is graduation because you've been doing this now for ages?' He's very impatient."
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Emma also revealed that she is a bit of hoarder and "one of those people that just keeps everything." The Paris-born starlet has 30 journals and has been recording her thoughts at night since the start of her acting career.
"When I got the Harry Potter part, it was my grandparents who said, 'You should write down what it was like to audition, what it was like when you found out you got the part so that you don't forget,'" said Emma. "And I just kept it going."