The Constitutional Law Professors blog has this post with President (then Professor) Obama’s 1996 constitutional law exam along with feedback.
The exam consists of two questions. The first deals with equal protection and substantive due process, and the second requires students to argue both sides of an affirmative action question and discuss theories of racial justice.
The exam is open-book, with six hours allotted. But in his instructions, Prof. Obama says
The exam is designed, however, to be completed in approximately three hours. Feel free to use the extra three hours as you wish (anxiously flipping through the casebook for that one last citation, or heading over to the gym for a good workout – your choice).”