Why is girls on the Run so much fun? Girls on the Run is so much fun because while you are participating in it you are making friends, encouraging others, learning lessons, and trying to complete your goal for that day. During girls on the run you have to know our most important rule, being respectful. It is our most important rule because sometimes we are not always showing each other respect. We are getting to know our teachers and they are getting to know us. The lessons that we learned and the ones we are going to learn can take us far in life, as we grow up. These are examples of why I believe Girls on the Run is so much fun.