You are a 1:1 school and the Internet/Network just went down. No need to panic! Take a couple of deep breaths and know you can continue on with class. Most of our teaching material is housed in an LMS (such as Schoology) or on a website. So you panic and think that students are not going to be able to work or do their homework.
Wrong! I suggest keeping 1 paper copy of your worksheets on hand for a "just in case" moment. In this situation, you are able to have students pull up an app like "CamScanner HD" and scan the worksheet. The app takes a picture of the worksheet and turns it into a PDF. After the worksheet has been made into a PDF, student can open in Notability (or whatever program you use for annotation) and complete their work.
There are plenty of apps students can use that do not require the Internet. I am assuming you still have textbooks in your class (at least most of the schools I work with do). Quizlet is an app that students can use to create flashcards. Have students go through the chapter and create vocab flashcards or flashcards about things they think may be important. Take notes the "old fashioned" way -- remember, on the whiteboard? Students can still use Notability to take their notes.
How about you? What have you done in an emergency situation when the network/Internet goes out? Please leave a comment below!