This is called a Desired Results Development Profile (DRDP) they have them for infant/todler (0-36 months), preschool (36 months-60 months), and school age (5 years and up). They help you understand at what part of development the child is at in every domain and shows you what the signs of it include and what the next level would be. It is used to help create curriculum for children who are doing well in some areas but need help in others. and you can always keep it in the child's files and do a new one to see if they are continuing to grow. It is also used to help teachers see if their is any concern they need to talk to the parents about for intervention before they start school.
http://www.wested.org/desiredresults.../form_drdp.htm
They also have little key chain ones that you can use to make little mini notes when it is not possible to sit down and document everything.