If you want to learn music theory, here are three of the best go-to websites.
On the homepage you can choose from three drop down lists: 1) Lessons, 2) Trainers, and 3) Utilities. The whole site provides flash-based interactivity.
Lessons take you step-by-step through topics that include scales, meter, chords. The lessons are additive, presenting the next relevant piece of information step-by-step as you click forward. The lessons are simple and clearly presented, great for explaining musical concepts to someone without any musical background.
Trainers programs are interactive, flexible and effective, testing your knowledge on concepts learned in the lesson area. A score keeper tracks correct and incorrect answers as well as your overall success. The trainers are flexible, allowing you to change the difficulty level or focus of the drill and practice time.
Utilities includes a chord generator, a staff paper generator, and a matrix (12 tone row) generator.
Arcade Games – The arcade games at MakingMusicFun.net are are interactive and effective, as are the trainers at MusicTheory.net, and add some graphic appeal for children. Eek! Shark! provides for the development of note naming skills. The game is colorful and flexible, allowing you to change the difficulty level in the set-up stage. Music Press Distress offers practice in rhythm recognition and values.
Printable Worksheets – A variety of note name and interval worksheets are available to print free. All of the worksheets are designed to introduce and drill basic skills.
Music Lab – The Music Lab on the San Francisco Symphony Kids website is graphically dazzling. The lab will effectively introduce kids to the basics, and then moves on to tempo, rhythm, pitch, harmony, etc. It winds up with a Composerizer that lets kids organize prewritten measures to composer their own piece and hear it back.