Another way to save web pages for offline reading is by using an app like Pocket as John Bean suggested.
I love Pocket! Install the app, create an account then when you want to save a page, you can "Share" it to Pocket. When you open the Pocket app it'll download all the pages you've saved to it, so you have to plan ahead to do that before you're offline. There are also plugins for desktop browsers like Firefox, for example, so you have access practically everywhere.