Here's part two, adult students. There are a few "brands" of adult students, so to speak. I am not going to address college students - these are "kids over 18" in my opinion. The adult beginning voice student - called by my local NATS Festival "Late Bloomer" category, can be comprised of older, retired adults, adults who study after work for fun, those trying to get into a community choir, or feel better about church choir, and you may have that adult who is longing to perform on America's Got Talent. They will have varying needs and you are going to need to understand how much of their lesson is recreational and how much is serious.
Private Students and Music TheoryWhen we want to introduce theory to adults, how do we do this without 1) seeming condescending, or 2) taking time from vocal technique, which is WHY they came to you in the first place. I have found that when adults begin taking music lessons, it is because they really love music and singing, and are trying to get over a technical hurdle that prevents them from fully enjoying singing. More often than not, these are the students you may need to guide through practicing. Occasionally they will have done some music in their youth, but maybe not. They may have rusty music theory from piano lessons, or not have any background with music theory whatsoever.
So, do we recommend that adults take outside piano lessons? Do we introduce theory as we go along? Or do we pick our battles? I tend to recommend self-study. I understand for adults it is often a struggle just to get to voice lessons, practice those songs, and go about daily life. But some, like retirees with a little extra time, want to soak up everything they can. I think a great self-study book is essential. I wouldn't hesitate to recommend the same book to some of my adults that I use with kids.
Theory and Sight-Reading for Singers has been a great find for my studio. It introduces basic concepts chapter by chapter, and for my young girls and teens, we sing through the sight-singing exercises and they can ask questions, but it is truly designed as a voice lesson supplement. Teacher guidance with this book is extremely helpful, and there are two part exercises to practice singing harmonies.
Alfred's Essentials - Self Study: If you know your student is going to work on things on their own, you can recommend a self-study theory book. Even with the best students, I think without guidance it can easily get put aside. But, I was impressed by how much ground the Alfred Self-Study covered. If they are serious, taking piano and voice, and want to understand, this is a good avenue. It has the CDs, workbook pages, and in the back there is a full answer key.
Group Lessons/Choir Music LiteracyI direct an adult church choir, and this is a challenge. I have a retired choir conductor and retired professor who can sight read anything, some men who play piano and guitar, and a handful of adult singers who would rather have a lyric sheet. My first step to get evryone up to speed is to offer three introductory theory sessions. JUST basic notation and some simple sight-singing. I feel like those who don't need it shouldn't have to do these exercises, and I'm on a limited amount of time for teaching theory for the majority of the liturgical year, because we must sing anthems for church. Luckily, after Easter it gets a lot quieter and we will be winding down for summer, perfect time to give them something new to do!
We are going to work through Alfred's Music Theory, Book 1. I liked this book because it's straightforward, cut-to-the-chase, and cheap enough to buy with my church music budget for whoever needs one. I was very impressed with the depth of the self-study book for private students, so I decided we will try the class book for choir. The lessons are almost identical, the only thing about the Book 1 is that you don't get the ear training CDs or the answer keys, so if you don't plan to spend much time DURING lessons on theory, then talk your student into the more expensive self-study so that lessons can be focused on technique. For classroom teachers, I LOVE that this book has a teacher book of reproducibles. When I worked in the classroom, it would have been perfect when needing a sub! Middle school and up could handle it. :)