Here is my meaning of Hellen Keller's quote:

It means that by using my voice I can do something. I may not be THE one but AT LEAST I AM one. I know that I can't do everything but the thing is, I CAN do SOMETHING. I will do what I can do to make a difference.

I don't know if that make sense or not, I have to give this speech tomorrow and I'm kind of struggling with the conclusion.

3 answers

Yes, it makes sense. However, you've just emphasized some words in the original quotation.

This discussion may help you. Please note that it's believed the originator was Edward Everett Hale.

http://en.wikiquote.org/wiki/Edward_Everett_Hale

Note the last line of the original quote.
Is there a different way to explain the meaning of the quote?
Each person can do something to help others.