What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
I am not sure if I have understood your question correctly. Do you want to auto generate a unique student number or you want to ensure that your form users input only a unique student id?
If you want to auto generate a unique student number, you should add a "Unique ID" widget in your form which will auto generate a unique number. You can further customize it by adding prefix or number padding. The following guide should help you: http://www.jotform.com/help/79-Add-Custom-Unique-IDs-to-your-Form-Submissions
If you want to ensure that your users only input a unique student ID, you can make the student id question a "Unique Question". This will prevent users from inputting the same student id again. The following guide should help you: http://www.jotform.com/help/223-How-to-set-Form-Limits-Based-on-a-Unique-Question
Hope this helps.
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