The biggest tip these videos suggest that if your child is having difficulty manipulating and/or working on assignments in Google Classroom from your home device is to ensure that no matter what browser you are using, visit www.google.com first, and then you may continue navigating to Google Classroom from there.
Using iPads: it is suggested to download 2 free apps which are "Google Classroom" and "Google Slides" (is this applies to your child's assignment.