Any new perspectives on Bible school programs?

Here are two problems that I have experienced in smaller churches since I have been working with education programs:

1. Shortage of teachers. No one wants to teach and older Christians invariably say they've done their time.
2. Gaps in Age Divisions. I'm speaking mostly about children's Bible classes here. One traditional age range will have lots of kids, e.g. Holley's class here has 7-9 kids in it. Back in Kosciusko, it had only her. However, other age ranges have 1 or no kids. The problem occurs when you put a 5-year old with a second grader who knows how to read and has been in school for a couple of years.

I am tending to believe that the problem may be our approach to the Bible school (Sunday school) program. The Sunday school is definitely based on a public school model where kids are divided into classes by age and the bigger churches (especially Baptist have historically had great success with it. It works if you have lots of kids and volunteers. But, that creates a chicken-or-the-egg scenario. If we had more kids and teachers we'd have a better program. But, if we had a better program, we'd have more kids and parents who could become teachers.

Is there another way to envision this? Does anyone know of another model?