An essential follow-up to Parker & Humphreys's first book about number talks. In Digging Deeper, the authors explore frequently asked questions teachers have about number talk routines. Videos from across the grade levels make up much of the book, which were extremely helpful to see number talks in action. It was easy to navigate the eBook, as the video links were clickable, but I am not sure whether a paper copy would be as user-friendly (links are presented in-line as URLs and also QR codes).