Do you have littles? Or grands? You need one of these! Have you seen the lovely growth charts at dearlillie.com? She is always sold out! And I'm too cheap to buy one anyway. But either way, if you want one for yourself and can't get it (like me!), then make one! It's an easy and fairly quick project.
Start with a six foot piece of "white wood." When I make a sign, since I don't have a digital cutter like a silhouette or cricut, I do it the old fashioned way: print up your number on the printer and trace onto your board with graphite paper. The paper lasts forever because for this type of thing you can use the same piece over and over. Next get out your paint or just fill in with a sharpie. My mom did most of this project for me when the last baby was born. Thanks Mom! She used a wooden school ruler as a guide and made marks for every inch. In hindsight, we should have started at 6 inches so kids wouldn't be forever knocking it off the wall, since part of it sits on the floor. Apply your favorite stain. I used minwax pecan on this one. Put a sawtooth hanger on the back and your done!