In general, large flight academies/universities and smaller FBO flight schools are the two categories of schools to look at. I started out at a smaller flight school. Advantages were that I got to fly with alot of interesting people, ranging from a Korean War vet who flew F-86s, to a CHQ mechanic (didn't know I could use that in an interview later), to a Lufthansa FO who wanted to rent one of our 172s to tour the state. I taught students from several different countries who were getting JAA license conversions. Also flew formation with a Stearman biplane while a filmmaker rode in the back, making a documentary, and I got a free ride in the biplane afterwards out of it! Also, there is the feeling of independence you get at a small FBO (in most cases). You take care of your own paperwork, decide when and how lessons will be conducted, find your own students, arrange your students' checkrides, etc. Keep in mind those items can vary GREATLY by the flight school you work for though. The main disadvantages were lack of resources, particularly complex and multi engine airplanes, airplanes that were either constantly booked or down for maintenance often. Also for about the first 3-4 months I was flying on average maybe 10-15 hours/week, barely getting by financially...you may need a 2nd job for a while, that's how I got through it. It is tough to find your own students sometimes...involves alot of hanging around the airport and greeting visitors, placing ads, etc.

About seven months later my alma mater called, so I began working there (large Part 141/142 university flight program). The main advantage, of course, is a never-ending supply of students...we are ALWAYS busy. Also in general the benefits are MUCH better (health/dental, life insurance, tuition waivers, personal leave pay, etc)...many small flight schools have none at all. Also the equipment is immaculate, maintenance is the best. Sometimes we still have issues getting an airplane (there are 10x the airplanes, but also 10x the students). However there are also disadvantages: Large flight schools usually fly out of larger, busier airports, thus more delays, thus higher flight costs and less happiness from students. Also there is that feeling of someone always looking over your shoulder, and there is a lot of red tape to go through sometimes to get things done. The larger a school gets, the more departmentalized it gets, which leads you and your students to go to five different people to get the same task you could do yourself at a small school. All this is very generalized, but just talk to some current instructors and students about the places you're interested in to get some inside info before applying. Good luck!