Obama's college records are not sealed.
They are not public, but that's because of the Buckley Amendment, a law proposed by conservative stalwart Jim Buckley (Bill's brother), which takes the libertarian view that individual privacy should be protected by all schools, public and private.
Why do some people need to make up hoaxes, like the hoax that the president's great grades are sealed? (Sealing would require a court order, and that would be public record. You claim they are sealed? You're a liar until you produce the record of the court that sealed them -- and there is no such record.)
Occidental's professors say Obama was a great student. Same at Columbia, and Harvard.