At Berkeley Middle we use a system to measure your child's reading known as the Lexile Framework. There is an associated number on our parent letters that go home during Report Card time, and this number takes a little bit of help to understand.
This video is a great place to start to better understand how your child's Lexile Measure helps your child.
After the video these few more articles are a good place to answer any simple questions you might have such as "what does my child's number mean?"