Furthermore, while in high school I volunteered my time in a Convalescent Hospital. I also assisted the elderly with daily struggles and organized fun social activities such as dance and exercise classes for them to enjoy.

as a question of personal taste, I would use neither ‘furthermore? nor ‘moreover’ (as Katerine W. suggested). To my ear, they both sound a little formal. perhaps ‘in addition’ or ‘also’ would be a little more apt.

by the way, I don’t use many capitals on the net, but that’s laziness!

convalescent hospital (you only captialize proper nouns such as, Reseda Convalescent Hospital).

Other than that it seems ok.

At least there is nothing seriously wrong like a dangling participle.