school council

I am currently on my school council as I have always loved to be apart of school activities and leadership. However a great deal to leadership is public speaking and although I can write excellent speech's my performance is often hindered by my nerves. I usually turn down opportunities to speak in front of my school because I am too nervous but as I wish to be a high positioned school leader e.g. school captain I believe I need to overcome my fear. Recently when I have spoken on stage my leg begins to shake and it is usually very visible. This is generally my main concern however at times I am too focussed on my nerves and not on my speech which can make it seem dull.

I do not wish to quit the council but at times I wonder if that would be better than facing going up on stage. I believe that I am too worried about what people think of me. Thanks.