I teach Music Theory (and piano) for a living-- this is an excellent introduction to the most practical concepts.<p>I was somewhat disappointed that the OP showed us a C Major scale without really explaining what a "major scale" is-- a collection of whole and half steps-- especially since they used a keyboard as an example, which is laid out in exactly the right pattern for teaching the major scale. (Notice that the black and white notes are arranged so that you skip some keys-- whole steps-- but sometimes you can't: half steps). I always teach how to build scales based on this pattern- WWHWWWH. Using this pattern, you can build any major scale beginning on any arbitrary note-- including notes that are sharped or flatted, which is neat. From here, you can figure out all of the scales, and thus all of the keys.<p>The advantage of learning in this fashion is that you can tackle <i>intervals</i> first, which are the distances between notes. (Note that major and minor intervals are named as such because they fit into our major or minor scales). Since a chord is simply collection of intervals, you end up with a more powerful understanding of them by learning which intervals (and which scale degrees) build which chords.<p>All the same, I really think the more "practical" approach here is really interesting, because you can start writing music earlier, albeit mostly in C Major.<p>Cool link, it really gives me insight as a fellow music educator.