The render_common_form_elements function was removed in the base class and it's contents put into the render_form_element function. These changes mean that some elements may not be required to override the render_form_element function, such as the studentname element, where this function was removed.
Rather than using grouped elements which can span across multiple lines on a small screen, the elements are now generated within a header element, keeping them separated and making the form more manageable. The base class was also changed to accomodate this by making it easier for elements to utilise common features.