ROTC served as an "overview training" on Military Science. All grad of ROTC are Reservists in the military. It somewhat prepares our people to become familiar with military discipline and chain of command. If the sovereignty of our motherland is invaded, we cannot resist effectively without a good pool of trained Reservists.
In my time, we had a Citizen Army Training (CAT) in high school. In college we had Reserve Officers Training Corps (ROTC). We were taught how to do proper marching in formation, how follow chain of commands, how to fire a gun, how to read terrains on maps, how to care for wounded comrades, etc. Ngayon wala na, NSTP na yata wherein the youth are trained to render non-military community services.
Trust me. the CAT in high school and ROTC in college is fun. It is one of my memorable experience as a student.