Rule Acknowledgement System
It would be nice for the site to give a simple pop-up before a user grades homework or utilizes chat/the forums so they are aware of the rules for each feature.
For instance, if someone wanted to grade homework, a little pop-up will appear that will re-direct them or show them the list of grading rules. In order to pass this pop-up, the user must press something like I Understand or I Agree before they are able to grade homework. This can help prevent users from grading assignments incorrectly.
This can also be extended towards topics and the chat. Similar to the homework pop-up, a link or list of rules will appear and the user will have to click to acknowledge it. This will provide users with direct access to the rules while also preventing users from stating they are unaware of certain rules when it comes to chatting and completing topics.
While I'm aware many people might treat this as a bit of a "Terms of Service," it may help reduce the amount of people claiming they were unaware of the existence of a rule when reminded. It can also help users who may skip over their welcoming message with direct and easy access to site regulations prior to their use.
Customer support service by UserEcho
Isn't there already that when you start grading?
I believe this is on a site-to-site basis (a pop-up does appear but some sites don't utilize the text within it)* and the button doesn't really ask you to 'confirm' or 'acknowledge' the rules. Instead, it allows you start directly into the tutorial with the 'Star Intro' screen. This is not what I am suggesting although this pre-existing feature could probably work out well with implementing my idea.
While a minor change, it might be helpful to include or change the wording of the button or add a checkbox for people to confirm they've read it. This can be similar to how the Buy VIP button works with the user having to check 'I accept the terms and conditions' with the list of rules appearing before you are able to close it (and check the box).
* I'm not on all of the sites but in the case of the two biggest sites, P US does not include any indication of the rules (their pop-up was essentially empty) last time I've created a new account and O has a brief note that if you grade incorrectly, you'll be punished. In none of these cases are the Grading Rules linked nor are specific rules mentioned.
As somebody who grades a lot, I wouldn't mind it if more detailed rules showed every 50 or so assignments to freshen up my knowledge. Or only once after grading 10. Everybody is overwhelmed the first time and rules are not exactly the same across all sites.