Starting in Kindergarten, put the child's graduation year on a large tshirt. Take a picture each year with same shirt to watch the child grow into the shirt. Display at graduation girl boy kid Baby kid
PLAYROOM : Here's a really cute idea. Frame quote bubbles, use a dry erase marker to write funny things your kids say. When you are ready to switch the quotes, have the child take a picture with their quote and make a photo book of quotes.
Trace their hand on their birthday every year on the same paper. (It will make you cry. They grow up so fast! Wish I would have thought of this. Maybe one hand in plain pencil and one in a different color pencil for each year.
DIY busy board full of switches, latches, and doo-dads for babies and toddlers to manipulate. This is great for fine motor skills. It is also a hazard for giving escapee toddlers the skills they need to get out unsupervised.