'Just began 13th year as religious education (pre-Confirmation) instructor of 8th graders in demi-affluent metro Chicago burb. Ergo, all scheduled encounters with them are in "church-y" setting.

Applying equally to age 13-14 young men and ladies...

...because few, tragic, pathetic few, have even the faintest idea they ARE young men and ladies. Or how to conduct themselves as same.

Without getting deep; foremost personal recommendations for your course:
* NEVER wear athletic /athletic-uber-casual attire to church or social occasions; learn to dress oneself
* Learn the hierarchy of the universe and defer to same; manners and politeness must be learned as much as game rules
* Do not be in such a frantic hurry ALL THE TIME. Take time to listen, form one's thoughts before blurting "something"
* BE where you are; play with your phone or whisper secret banalities to your colleagues some other time and place

Best of fortune in your noble quest.