text: Ask her about her activities over the 2 or 3 days before, and the day of the shin pains. I went through this with one of my children when she was in elementary school. It took about three months, but I finally spotted a pattern. The school rotated the playground activities on the lunch and recess breaks every week and about once a month the area my daughter played in for a week included the monkey bars. They were her favorite part of the playground equipment and she climbed them constantly during the time allowed. To check my theory that this was the cause, I forbid her to climb them the following month and she didn't develop the shin pains. After that she was more careful not to over extend herself on them (so that I wouldn't take away the privilege again), and all was well. We had the same problem when she got her first bicycle, until her legs got stronger.