
1) Amirs 2) Dynasts 3) Measurers 4) Monarchs 5) Regents 6) Straightedges
Found on
https://www.crosswordclues.com/clue/rulers

1) Classroom tools 2) Drafting aids 3) Drafting class supplies 4) Drafting tools 5) Emir and despot 6) Foot-long school sticks 7) Grade school staples 8) Heads 9) Kaisers or czars 10) King Tut and Nefertiti 11) Kings and queens 12) Kings and queens, and others 13) Kings and queens, etc 14) Line gauges
Found on
https://www.crosswordclues.com/clue/rulers
No exact match found.