Many a time student animators set their aim on the stars to discover the weight of the sky crushes dreams.
In other words, when an animation teacher suggests planning a short animation as a step toward greatness, it is done with concern for the student's well being. That is why in-class exercises are short 60, 120 to 200 frame animation sequences (usually of the bouncing ball variation).
Then when an animator is set loose on their major project in second year, they can have a full appreciation of why the teacher keeps suggesting to keep the story to 1 minute, or less. This hurts, especially for animators who dream of animating a 4 minute music clip*.
"But what kind of story can you animate in less than a minute!?", is the outcry.
DreamWorks made an excellent film this year that we explored on an animation field trip. Here are some animation lessons, disguised as dragon training lessons. They're all less than a minute long. Actually they are only about 30 seconds long including titles and fades.
*The trick for animating a 4 minute music clip is study the song and animate for the verses (same beats) and chorus (repeated over and over). Then loop and edit the 30 seconds of animation together in interesting ways.