We know he was a Political Science major at Columbia. That is usually not thought to be a very rigorous field of study. More importantly, though, we also know he did not graduate with honors. That means his GPA was probably in the "B" range at best. While that is perfectly respectable, it DOES NOT get you into Harvard Law School -- not now, and not in 1988.
With those college grades, 0bama had to have been an affirmative action admission to Harvard. That's why he won't release his college transcripts.
As for Harvard Law, I have seen reports that he did receive honors there, but, if that is true, I have to wonder why he didn't receive offers of judicial clerkships. A summa cum laude from Harvard Law would normally be offered a Court of Appeals clerkship, typically with a judge who was a "feeder" to the Supreme Court. Some Court of Appeals judges are regarded as good talent scouts by the Supreme Court justices. Those judges will take on top law school grads as clerks, and, if a clerk proves to be good, will then "feed" that clerk on to the Supreme Court. 0bama may have chosen to opt out of this network, but there is no report I have ever seen that he was even given an offer. That causes me to be skeptical about reports that his grades were very high.
Then, of course, there is the Harvard Law Review. Although the sycophant press often reports that 0bama was "Editor in Chief," that is not true. He was "President" of the HLR. The President is elected by the student body, whereas the Editor in Chief was chosen by faculty advisors and fellow HLR Editors for academic excellence (often first in class, always among the top four or five) and quality of articles done for the HLR. 0bama did not serve as an HLR Editor and had no articles published. He would never have been considered for Editor in Chief.
Bottome line, 0bama has put forth a carefully tailored resume, but it won't bear much close scrutiny. That's why he has to be so secretive about his college and law school days.
He was not summa, he was magna. How much of this was merit, and how much his people skills is a matter of debate.
As for his admission to the law school, did you miss the disclosure by the bigtime Harlem politician/HLS alum that he had intervened on Obama’s behalf—allegedly at the request of a radical political activist who was raising money for Obama’s education?
Of course the Obama campaign denied it.