Another pinner: Measurement -- Longer/Shorter. Easy for my five year old but good practice for her to work independently. Was surprised my two year old sorted and match the lines on her own the way they are in the picture. Super easy to put together.
Cute idea for measurement common core- do a few times a year. Read Big Dog, Little dog, and then measure each child to see how tall they are. Make a chart for display, and leave out the measuring tape for a few days!