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I've had a MacBookAir 11'' for two years now, and I also strongly recommend the 13''. The thing is, you're going to be sitting at school and looking at that small screen for hours and hours for several years, and 11' is limiting no matter how you angle it. Working with 13' will be much more satisfactory and practical, and the 13'' is also very lightweight and slim.
Get the 13'' is my recommendation.
 
- a lawyer's craft is in writing and formulating arguments, and also reading arguments. Often, when writing, you want to see the flow of ideas on the page, as one paragraph links with paragraphs above and below. With a 13", it provides adequate space above and below - but with the 11" widescreen dimensions, you get precious little height on the writing page.

The 11 is lighter and easier to carry when chasing ambulances. :D
 
The 11 is lighter and easier to carry when chasing ambulances. :D

Those sort of lawyers chase ambulances so that someone will pay them enough money so they can afford shiny MacBook Airs on which they can write their arguments.
 
I have the 13" 2011 and love it. There have been a few select times that I wish that I would have purchased the 11" for class but there have been many more times that I am glad that I chose the 13" instead. I think that the 11" can have it's uses, but I think it's for more niche users. If you want something you can use more outside of class then go with the 13".
 
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