For any online assignment, I give my high school students until 3 pm the following day to complete it (more than 24 hours). I check completion before class and touch base with students during class to confirm that I saw that they did it, or to remind them to do it. This is also useful if they have technical difficulties and need help figuring out the problem. For students that don't have internet access at home, I tell them that they have to take responsibility for doing the online assignment at school, where they have access to computer labs all day long. By giving students more than 24 hours to complete an assignment, they have the opportunity to use free periods, lunch periods, after school time etc to access the internet, and to let me know if they had difficulties with the technology before the assignment is due. It's worked for me in the past.