It's nice. And I guess considering the text files, it's quite complex!
The function_call program: We can put other things than a single number. Even entering nothing, works. So maybe manage to handle exceptions.
The rock_paper_scissors and same seed program: Should redisplay and start typing a digit 0,1,2 again if "invalid input". Without leaving and handing over the order.
The string_input program: Contains a string limit.
Of course, these are only details that do not totally deserve importance ^^.