I'm teaching someone to code right now on the Raspberry Pi, and JupyterLab is working far better for us than IDLE or a separate text file and terminal. We use the workflow described in http://jupyterlab.readthedocs.io/en/stable/user/documents_ke.... We open up our python file and a console side-by-side, and pressing shift-enter in the file sends a line or selection to a console. We can easily investigate it in the console outside of the file too.

You can just "pip install jupyterlab" on a Raspberry Pi and it works great!