I would argue that introducing such concepts in easy to understand ways is the task of the IDE for such learning languages. E.g. Thonny does a great job of explaining how locals work during debugging by using a multi-window mode where each stack frame gets a separate window that shows just that function's code (with current statement highlighted) and its locals. It also takes care of recursion - you can easily see how every recursive call adds a new window, and each window has its own set of variables.