I realize that this isn't a 'tech tool' however it's an important discussion. I am adding this page because I received information about a course from CIRA (Canadian Internet Registration Authority) on Cybersecurity practices for remote workers that looks like it would be important for teachers and students who are doing distance learning.
Securing your home Wi-Fi
VPNs (Virtual Private Networks)
Protecting confidential information
There is also a PD course available for training staff.