Soundproofing your teaching room
There are acoustic treatment solutions for absorbing reflection. For a studio these do calm a room down well but offer little sound-proofing. You probably already know about rockwool and other layers you need to put behind the plasterboard. I doubt you need to go that far if you want to only teach in it. For a controlled room it involves bass traps for corners, esp behind speakers, and proper sound density absorbing foam (don’t skimp with other softer types) designed spreadout across the side walls and back. You don’t need to over do it. You can even get thick flooring if you need to but not so highly important for just guitar. For any amp you can place these on thick foam pads (careful of heat). You need to see examples of how they disperse foam in a room. It doesn’t take much to calm it down then you’ll notice how hard you must push your own voice to be heard. It can get very hot as foam changes sound into heat! You will need air-conditioning with ventilation to avoid any problems in summer. We highly advise this as otherwise you may find yourself getting severely stressed.