Ok, this is me playing with google docs.  I had no success before, but maybe this will work.  I use this cover for our snowflake books.  I have cut out foam snowflakes from a craft store on the frame next to my door and I have numbered them 1-20.  I have the children estimate how many snowflakes tall they think they are, then I measure them, they record how many snowflakes tall they actually are and then I take a picture.  Here is a link to the googledoc if it works  Snowflake book cover