Course
    User -- a user of the system (minimally implemented)
        
Course
    Session -- a login/do some stuff/logout group, maybe should be under User

Course
    Generic -- AUTOLOAD and some random catchall like database handle and 
        cgi object 
    
Course
    Assessment -- an assessment, possibly split up into segments, 
        each segment consisting of one or more questions 

Course
    Assessment
        Segment -- a logical piece of an assessment, e.g. the t/f part or 
            the essay part

Course
    Assessment
        Question -- one item of an assessment, possibly with multiple segments

Course
    Assessment
        Question
            Bank -- repository of questions


Course
    Assessment
        Question
            Segment -- constituent parts of a question
                Text
                    Instructions  -- not part of the question ("answer in 
                        complete sentences", etc)

                    Question -- the text of, for example, an essay, 
                        m/c or t/f question ("What color was George Washington's
                        white horse?")

                Input -- the part that the student fills in

                    Essay -- a space for a long textual response

                    Fill_in -- a text field embedded in a sentence

                    Multiple_choice -- radiobutton group of choices
                    
                    Order -- 'Fastest finger" type question
                    
                    Segment -- a piece of, for example, a multiple choice input
                    
                    Short_answer -- long text field
                    
                    True_false -- fixed radiobutton group
                    
                Libob -- library object (set of data, book excerpt, etc)
                
                    Blurb -- piece of text for questions to refer to
                    
                    Image -- image to be used as part of a question

The following are pre-set templates for common types of questions, 
for convenience.

Course
    Assessment
        Question
            Essay -- question::segment::text::question, 
                question::segment::input::essay

            Fill_in -- question::input::Fill_in

            Multiple_choice -- question::segment::text::question, 
                question::segment::input::multiple_choice

            Order-- (unimplemented)

            Short_answer -- question::segment::text::question, 
                question::segment::input::short_answer

            True_false -- question::segment::text::question, 
                question::segment::input::true_false


Response-related classes:

Course
    Assessment
        Question
            Response -- for storage, display, and checking of student responses
                Segment -- each input segment gets a corresponding response
                            segment
                    Essay
                    Fill_in
                    Multiple_choice
                    Order
                    Short_answer
                    True_false