Hmmm . . . . .
A 24x10 matrix board, a 8051 based MCU that supports serial programming with a simple TTL level cable, a 4 digit LED with a few extra indicators, three switches, a beeper and a 4 way header, all for about $5 Mount the display off the board edge to free up some space and you've got the basic student hardware for an introduction to microcontrollers course.