[CO] My retired piano teacher who sexually abused me has started teaching children again. I fear that she intends to abuse other children and I want to stop it. I have proof of her abuse against me. How do I go about this?

Between the ages of 9-11, I took piano lessons with a teacher who sexually abused me. If memory serves, I believe that she did it almost every week for the 2 years that I took lessons with her. The only reason I stopped going to her was because she retired.My teacher used to take photos of the abuse (polaroids), and would give them to me, under the guise that it was "our special secret". I won't get into specifics, but I have possession of several photographs of the abuse where both me and my teacher are clearly identifiable.I never told my parents or anyone else about the abuse or the photos due to immense shame and guilt.Recently, I found out that this woman has decided to start teaching again, but specifically becoming a children's instructor. I am absolutely certain that she intends to hurt more children just like me, and I want to stop it before it's too late.So my question is: legally, what can I do and what should my course of action be? I don't want money, I just want her stopped.I have the photographs, but I am worried of the legal repercussions of having them in my possession, as they are technically child pornography.Please walk me through this, because I genuinely don't know what to do, and I'm scared she's going to hurt someone else and it will be all my fault because I didn't stop it sooner.For reference, I am 19 years old and I live in Colorado via /r/legaladvice https://ift.tt/2zs9tsl