If your internet access is limited you should use the Plus mobile app. With the app, you can download courses when you do have an internet connection and then complete them at any time offline without an internet connection. Next time you connect your Plus app to the internet, it will synchronise with your Plus account so that your learning activities are updated in your account. More information on the app here.
If you have limited internet connectivity, you can also listen to the audio or reduce the video quality. For more information, click here.