Thank You Notes: A Children’s Story about Exponential Growth is an open-source children’s book in pdf form now available at
https://www.merlot.org/merlot/viewSite.htm?id=9162542 and at NGSS@NSTA Hub, Intended for children in grades 3-5, this book uses upper elementary students’ skills in multiplying by 2, adding multi-digit numbers, and creating bar graphs. A guide suggests ways for teachers and parents to help children understand what exponential growth is in a positive context separate from