13 boy how to ask for dance/ gymnastics?

I am 13year old boy and want to be a singer more than anything and take voice lessons so i figure most great singers can dance ( michel jackson, usher, lady gaga, p!nk) or some even can do acrobats on stage ( p!nk) and i already plan on asking my parents for poetry classes but i think i would also benefit from dance or gymnastics plus i am slightly over weight i weigh 135 and am 5'7 so how should i ask them and will my Friends tease me only one Friend knows about my singing and i would prob do dance with that Friend thanks