Working as a math coach, I have the privilege to work with many amazing teachers at various grade levels. In as much as I am here to assist them on their quest to conquer math as effectively as possible, I often walk away learning something as well. An primary teacher in Ogdensburg, NY shared a resource she uses in her classroom. It is a Youtube.com channel called KidsTV123. Here is a great video about shapes:
Here is one about measurement which could be used with older children: