Here is a good inexpensive “starter” acoustic guitar that comes in four different sizes. The smallest size is 1/4 the size of a full size guitar and is designed for very young students age 4 to 6 years. The next size is 1/2 and should fit kids age 7 to 9. The 3/4 size should work for 10 and 11 year olds, and the full 4/4 size for students 12 and older. This guitar can be purchased at The Guitar Center in Killeen, or online here: http://www.guitarcenter.com/Lyons/Classroom-Guitar.gc 

Classroom-Guitar