I agree that there should be a way for players to figure out when the next class would happen without having to look at the forum calendar. And as YeetChris mentioned, the /nc command used to show the countdown for the next class as a title in-game, but you seem to be new and that feature broke a long time ago - it was also a useful feature for players to use.
Also, sorry for hijacking your thread, but since this is related to class timers, I made a somewhat similar suggestion awhile back in the Uservoice suggesting that they should add an NPC (similar to the Tommy Riddle NPC) which a player can click on and it would tell them what the next class would be. This NPC would hopefully have the same countdown timer (seen above the Tommy Riddle one) which can show how long it will be until the next scheduled class would happen. --- But the staff reply to the Uservoice suggestion said that the "/nc command would be fixed when the new website is introduced" but I guess they haven't gotten to that yet.
Hopefully they'll have something similar to how /nc used to be when they release Revelius though.