Ask the experts
If one is not at risk for getting a disease, then why do they still insist on the vaccination?
How a particular disease is transmitted has nothing to do with whether one should be immunized (that is, vaccinated) against that disease. Whether the disease is airborne or whatever is irrelevant. What is at issue is whether immunization is the best way to prevent the disease not only from striking you but from spreading in the population.
Immunization programs help build defenses against disease. Immunizations should be started early and carried out faithfully. Immunizations are important, for example, with the 8 childhood diseases (measles, mumps, rubella, diphtheria, tetanus, pertussis, Haemophilus influenzae type b, and polio) that are preventable by immunization. All of these diseases can and do cause crippling and sometimes death; these are serious diseases and their complications can be terrible.
Furthermore, protection from a certain disease requires the specific vaccination for that particular disease. Vaccination for one illness does not provide protection from another. For example, vaccination for Hepatitis B does not protect against the AIDS virus (HIV or human immunodeficiency virus).
The fact that you are "a 53 year old who works at a high school and (is) in contact with 2500 kids" is all the more reason for you to be completely immunized. It is important for your own protection and for the protection of the 2,500 kids in that school.
Diseases for which immunizations are given tend to be highly contagious. They can spread rapidly from person to person and from community to community. As long as people remain unprotected against them, serious outbreaks of disease - even epidemics - can occur.
Generally, vaccines are among our safest and most effective medicines. Like other medicines, vaccines can cause side effects but these are these are usually very mild - a slight fever, a sore arm, a mild rash - and don't last long.
The overwhelming majority of medical experts in the U.S.A. and abroad believe that the benefits of complete immunization far outweigh the risks. The U.S. Public Health Service strongly recommends that all healthy people be immunized against all of the vaccine-preventable diseases. The health experts in many countries are in full accord with the concept that everyone who is healthy should be immunized as recommended.