Hi,
I am 23 and having been teaching for nearlly two years now. And i still feel that people think i may be too young to teach. But with my long-term students i have proved myself. organised a concert, taken them on a trip, had competitions and exam progress, so I am quite happy now that my students know i'm not too young. i do wonder about new students and their parents however. i had one girl start singing lessons, and her mum was always asking the students that she saw before or after if I was any good? but I have proven myself to her now and her daughter thinks im great!
You do learn a lot when you start teaching, my playing has improved, my vocal range has grown, my theory work is now really good (even though I did my grade 5, 10 years ago) I have a degree and grade 7 in singing and piano, and i feel much happier going into my grade 8's and i am looking forward to working on my diplomas.
I have to wait 2 years to do a teaching course for singing because you have to be 25, but i will be confident by then because I will have a lot of experience under my belt.
So I think it's great to start young as long as you can prove yourself. Because when i'm 30 i will have lots of experience and qualifications and will be able to charge top notch
thats my view anyway