TeachScheme! 2002

  Assignments: have them develop a three-layer piece of 
               their ancestoral family trees

               ;; all-blue-eyed? : ft-node -> boolean
               ;; determines whether everyone in tree has blue eyes

               ;; all-young-blue-eyed? : ft-node -> boolean
               ;; determines whether everyone born after 1940 has blue eyes
               [hint: copy then modify all-blue-eyed?]
               
               14.1.5 (p. 198)

	       [hide after this]

               ;; count-generations : ft-node -> number
               ;; determines how many generations are in the tree

	       14.1.4

  Optional for people going fast:
    - Descendant family trees (Sect 15.1, page 210)
    - Simulated Web pages: (section 14.3, page 204)
    - Interpreter (section 14.4, 17.7)
    - list of structs/graphics (section 10.3)
    - binary search trees