A tried and true rule of cartoon characters is that they don't age and often never learn anything. Heck, many of them always seem to wear the same clothes for year after year.
However twenty years ago, Disney challenged this rule in the film A Goofy Movie. Max Goof was Goofy's young son on Goof Troop:
But in A Goofy Movie, Max Goof was aged to become a teenager:
Coincidentally, the next Disney character who would find himself aged got his start the same year that A Goofy Movie premiered- Andy from Toy Story:
By 2009's Toy Story 3, Andy was heading off to college.