I'm training on my own for my first 15km run (and hopefully, 21k also). My knees are getting better albeit still experiencing some pains once in a while. As my way of training, I've been trying to increase distance to put my personal limits to the test. My running friends suggested that I try the Galloway Method. It was named after Jeff Galloway, the famous coach runner. He intended the Galloway Method for beginners like me and the main goal of this method is to keep runners injury-free.
Basically, you just alternate running and walking until you finish the distance desired. Jeff Galloway suggested useful ratios between running and walking depending on your speed. You can see this in his website. However, if you do not want