Ask HN: Books/resources for a 3rd grader getting a Raspberry Pi 400

My son asked for a Raspberry Pi for his birthday (which is next month). He’s been pretty active and interested with Tynker and Scratch and wants to start playing with Python (and possibly other “real” programming languages). He asked for a Raspberry Pi, so I managed to find someone with the Raspberry Pi 400 in stock, but I’m guessing that we’ll need some good materials for young kids to explore Python and the capabilities of the Pi. Any recommendations? Ideally, I’d prefer books and offline resources as much as possible as 9 is a bit young to have free exploration of the net.