measuring a growing teen

When the kids were small, we used to measure their heights against a wall near the kitchen. We will write the name of the child and the date when he/she was measured. When we moved to the present house; we kind of regretted that we did not do anything to bring that part of the wall with us...I don't know how we can do it.

Every morning when Dan comes downstairs he will give me a hug with his cheery good morning. Early this year when I hugged him, he was up to my nose. Now he is taller than me. I decided that I have to keep tab of his growth....so we started measuring him again.
All he does is stand against this wall which is near the back door, I will put a pencil to the top of his head, draw a line across and have the date noted there. I wrote his name there because I thought we may be measuring others too but at the moment none of us are growing any taller. So no need to check on our heights.