[pygame] Current working version of Python and pygame

[Irv Kalb <Irv@xxxxxxxxxxxxxx>]

I am teaching a Python class, where I use pygame to demonstrate OOP concepts.  I need to have my students get the proper environment to run Python with pygame.

I use a Mac, and I have Python 3.7.3, and pygame 1.9.6 installed.  Everything works fine for me.  But I have students who either have Python already installed and need to install pygame, or who need to install both Python and pygame.  

I am not a Windows user, and I typically don't use the command line for anything other than installations.  My understanding is that if you are on Windows, and you want to use pygame, then during the installation of Python, when the installation puts up dialog box about installing Python, you must check the checkbox at the bottom that says:

     Add Python 3.x to PATH

Question 1:  If someone already has installed Python but did not check this box on, is there some simple command line magic to do whatever this checkbox does?  If so, what do I need to tell my student to do?

Question 2:  If someone does not have Python installed yet (or wants to install a newer version), what is the most recent version of Python (Mac and Windows) that I should ask them to install today?  I understand that there is a big effort to get the 2.0 version of Pygame out, but I want my students to use version 1.9 for now.  If they install the current version of Python: 3.9, will they be able to use pip to install a working version of pygame 1.9?  (Last time I checked, this did not work correctly?

Thanks in advance,

Irv