Profile2 allows a user to create and manage their own profile within Sakai. Users can also add connections, upload pictures, connect with Twitter and many of the other Sakai tools integrate with it.
Profile2 features a comprehensive privacy and preferences system and is massively configurable for your institution.
Profile2 also allows for official profile photos to be supplied for students, check the configuration to find an integration that suits you.
Please see https://confluence.sakaiproject.org/display/PROFILE/Profile2 for the full configuration.