Need idea: custom post type and custom meta

• To get the users who have the role called student, use the WP_User_Query object
• For storing the fields, use post meta just as you would on normal posts, remember to declare that your custom post type supports custom fields when being registered
• For your dropdown/etc you will need to register metaboxes

More info on WP_User_Query.

For how to add metaboxes see the Codex entry and examples for this function.