google chrome app kiosk issue: slow and loses student data

I am a teacher and I created a kiosk app for use in the classroom that simply opens the web page for canvas LMS (mde.instructure.com). Students log in to my class through the app to take tests. The problem is that it seems much slower than when accessed through the browser, and the some of the students' work is not being saved. Any ideas?

Here is my chrome app: http://ift.tt/2fctgRw