Students can change their passwords, but sometimes they forget what they changed it to, or have technical difficulties connecting even with what you think might be the correct password. You cannot look up their passwords, but you can change it for them.
While logged in to your teacher account,
1) Click the Classes tab
2) Click on the classroom where your student is who needs help
3) In the image guide below, Test Student 1 needs a new password:
4) Click Okay after typing in the password you want them to have
You can also reset all of the students' passwords to the same thing:
And then follow the same steps. You can then tell your student(s) what the new login information is.