Chances are, you’re already sitting on a lot more training material than you may think. It could be in books on your bookshelf that you haven’t read in a while. It could be something that you're already doing, which simply needs to be recorded and communicated.
Lastly, it could be a bit of vision that God has put in your heart that you simply need to share with your team. With a little bit of attention and planning, you can organize your materials and produce some outstanding curriculum. Trust me, your volunteers will thank you.