Please refer : http://helpx.adobe.com/x-productkb/policy-pricing/education-faq.html
Adobe Student & Teacher Editions require that you verify your academic proof after you receive the software in order to obtain your serial number. The instructions for this verification process are inside the box. Adobe Student & Teacher Editions can be installed and used immediately for thirty days before a serial number is required.
You will need to go to the Adobe Student & Teacher Edition Eligibility Verification website listed in the instructions, enter your product code (found at the top of the instructions), enter your contact information, and submit academic proof. Once your academic status has been verified, you will be emailed a serial number. This process can take 1-3 business days, but you can still run a trial of the software while you wait.*
If you would like to check on the status of your request, click the "Check Status" link on the left side of the webpage. If you have questions about this process, click the "Contact Us" link on the left side of the webpage and fill out the Contact Us form at the bottom of the page.