The debate I’m having with other math teachers is around what Common Core excludes: the emphasis is on “base 10” arithmetic operations, but minus any discussion of what “base 10” really means, as no other bases get mentioned. Exposure to bases 2 and 16 is developmentally appropriate pre 8th grade. The main issue, I think, is we use the wrong tools (artifacts). A real “Read Evaluate Print Loop” (REPL) is so much better than using a Texas Instruments calculator. “Use any core you like, just make sure you use a real REPL (e.g. Python’s) and not a TI” would be my advice.