I've also voiced the opinion that bible teachers can and, if possible, should learn some. At that point I said a hundred hours would not be an unreasonable investment of time.
Well here's a 40 hour course. Twenty lessons, one hour of homework a week.
It uses this textbook which has a CD-ROM with answers to homework exercises.
Thanks to Ros for flagging this up. I don't know the text book or the website but I know she's a great linguist so this is worth following up if you're keen.