Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Expand Your Landscape

This is a must read for any k-2 teacher. Primarily focused on K-2 teachers this book offers a direct and explicit document to base investigative math. It also gives clear research into the development of young mathematicians (the why). It is a short and concise book that gives you the framework to change your mind-set on teaching math. There is new support materials available as well. Read it and raise your teaching to the next level.