Ask at your local Apple Store. The way the education discount rules are applied varies widely, and the store may be willing to extend the discount to you, where the online store is not.
I recommend you do NOT skip the AppleCare warranty extension program for a battery-powered computer that will be transported around from class-to-class, and to and from school. You can put tremendous G-forces on the computer just moving it around.
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The previous generation of MacBooks are often available as Apple refurbished. Apple refurbished are indistinguishable from new, and are eligible for the same warranty and Applecare options. Stock changes often, so keep watching for a while.
You can have educational discount, or Refurbished discount, but not both.