Don't trust the RCI, and remember education is bad. With a city of 25,000 I have one elementary school and one highschool and education fluctuates between a healthy (40,35,15,0) to an unhealthy (25,50,25,0) or worse. Whenever you have a shortage of workers, build more residential. This does two things:
1) Helps fight recessions. See the thread on the front page for more info, but basically the game has a 6-year cycle where people turn into Seniors pretty much all at once and stop working. They clog up all the housing and make employees impossible to find. Building houses lets young immigrants arrive until the hearses can go Logan's Run on your deadbeat senior problem.
2) Raises unemployment by increasing the population. Unemployment is good. Anything below 5% and it will be hard to keep workers in factories.
This, at least, has been my experience.