(1) Rather than go into "Groups," go into "Classlist."
(2) Once you are in "Classlist," where it says "view by," change it from "users" to "groups."
(3) You can then go through all of the groups and then click on "print tab" and it will print the group list rather than the entire class list.
(4) You should have the option to "print" the list as a PDF file. This way you can keep a copy on your computer as well as printing one off in hardcopy.