First Congrats on your acceptances those are some great options. Also remember where to attend law school is a life altering decision and you should take any advice received on internet boards such as this, my post included with a grain of salt.
With that said I think any law student should consider the following five factors when choosing a law school in this order. (1) Location; (2) Cost; (3) Personal Feelings about school; (4) Understanding the Reality of Legal Education; (5) Last and Least U.S. Rankings.
The reasons for these factors are analyzed below. Location:
This is the most important decision in my opinion, because law school does not exist in a vacuum and you will spend a minimum of three years in the City you attend school. Additionally, odds are after three years during the prime of your life in a City where you have an apartment, make friends, likely enter into a relationship, take a state bar, obtain internships, etc odds are you will remain in the City you attend school. Obviously, there are exceptions to this, but if you attend Columbia odds are you will end up in New York; Stanford in the Bay Area; Harvard in Boston.
With that you have to ask yourself where you want to live. If your a California girl and want to be in California Stanford might be the best option. I don't know your personal situation, but if you are close to your family, have friends, are in a relationship etc those relationships will be impacted if you attend Columbia or Harvard by the distance. However, there is excitement moving to a new City and meeting new people, but only you can answer what is best for you.
Additionally, Palo Alto, Manhattan, and Boston are different places. I personally think Palo Alto is very boring and hate it I am in that City all the time. It is very safe and nice, but I like a little more chaos. Columbia is sort of near Harlem and a beautiful campus and you have easy access to NYC and it can be great. I have never been to Boston or the Harvard campus.
You definitely need to visit the schools and evaluate the Cities for yourself.
I imagine with these acceptances you can get scholarship money from these schools, but look at the total cost. I assume you will be taking out loans to pay for school and this money is not free
Stanford is 50k per year tuition 25k per year living expenses x 3 years = $225,000. Here is LSAC price link http://www.lsac.org/docs/default-source/official-guide-2013/aba4704.pdf
Columbia is 52k per year tuition 22k living expenses x 3 years = $222,000. Here is the LSAC price link http://www.lsac.org/docs/default-source/official-guide-2013/aba2163.pdf
Harvard is 48k per year tuition 23k per year living expenses x 3 years = $213,000. Here is the LSAC price link http://www.lsac.org/docs/default-source/official-guide-2013/aba3457.pdf
So looks like Harvard is the cheapest, but they are all roughly the same price. However, if you can obtain scholarship money from these schools that is definitely a factor. You may also be able to get full ride scholarships from other law schools.
Before entering law school you have negotiating power and don't be afraid to use it. Tell Stanford you are thinking of choosing Harvard and vice versa see if they offer you 5-10k scholarship. (3) Personal Feelings about School:
This is also very important every school has a culture to it and whether you like that culture or not is a decision only you can make. To determine if the school is a fit for you visit the schools talk to professors, students, admins, alumni and see how you feel after meeting them.
Also walk around the campus and the surrounding area. You will be spending a lot of time on campus and in those few blocks and you will either love it, be indifferent, or hate it. After visiting the schools you will have a gut feeling and it is important to listen to that.
(4) Reality of Legal Education:
Whether you attend Harvard, Stanford, Columbia, etc or some other ABA school you will be learning the same thing. You will be reading Supreme Court Cases and the Supreme Court doesn't write separate opinions for each school. No matter what school you attend your first year will consist of Torts, Civil Procedure, Contracts, Property and you will be reading Pennoyer v. Neff to learn about notice, Palsgraf in Torts to learn proximate cause etc.
Obviously at these institutions the professors will be phenomenal, but at the end of the day the law is the law. (5) Rankings:
Remember U.S. News is nothing more than a for-profit, unregulated opinion that is offering an opinion. Just because they say Harvard is better than Columbia this year doesn't make it true. Additionally, the rankings change every year and this year Harvard and Stanford are tied. If you actually look at the rankings you will see the endless ties and you can really see the ridiculousness of it.
Additionally, all of these are amazing institutions known worldwide so you would much better off considering location, cost, and personal feeling about the school when making your decision. Conclusion:
At the end of the day there is no right answer. I remember when I was a 0L deciding where to go I kept looking for something that would make the decision for me, but there is no way to know how it will work out. Maybe if you go to Stanford everything will go right maybe it will go horribly there is no Crystal Ball unfortunately although it would be great to know how it would turn out.
I really think once you visit the schools a gut feeling will develop and go with that.
Congrats on your acceptances and good luck whatever you decide.