Lots of things get called as “growing pains” but just because there is pain in a growing child does not mean it's a real growing pain. It is easy to dismiss pain in a growing child as growing pains. A genuine growing pain only happens during the night and never during the day. The discomfort is also in the upper calf muscle and behind the knee. If the pain occurs during the day and in another spot than the rear of the leg and knee, then it's not a true growing pain and is probably due to something else that should be investigated. Typically, it only occurs in younger children and awakens the child at night. There is no history of trauma or any sort of injury to the area that the pain occurs in.
Growing pains tend to be fairly benign and self-limiting, in that they do come right after time. However, they can be stressful to the child and parents at the time and, more importantly, there are several serious and uncommon conditions that may have symptoms much like growing pains, so each case does need to be given serious attention and looked into to eliminate the other possible causes. The implications of neglecting these uncommon reasons for similar symptoms can be significant.
The standard management for growing pains is simply reassurance of the child. They should be comforted and helped to return to sleep. Gentle massage or rubbing of the leg will often be useful. In some instances medication can be used to help the pain and ease the getting back to sleep. Stretches just before going to bed and if the pain happens may also be helpful. Of most importance is education concerning the nature of growing pains and that it will pass plus an evaluation of those potential rare and serious causes of the pain.