7/8 lessons

I think you're doing a really, REALLY wonderful thing here. But I feel like you need to do some more research on each topic.

You mention Pentatonic in Lesson 7 and being a misnomer - I think for the Scottish scale you list.

Octa, Penta, Hexa, etc. are simply prefixes for the number of notes a scale contains.

There are two basic Western Pentatonic scales:
"Major" CDE GA
"minor" C EbFG Bb

There are also "modes" of these:
C D E G A
D E G A C
E G A C D
G A C D E
A C D E G

Note these are "unnamed" though the first and last share the relative Major-minor relationship of 7 note scales.

There are also however common Pentatonic scales form Asia that don't have this same W W m3 W m3 pattern (C D Eb G Ab for instance).

You also mention there are only 3 recognized types - Diatonic, Chromatic, and Whole Tone. What about "diminished"? You need some better categorization here.

Where did you find the word "primitive" for the Natural Minor scale? Is it used only in Jungle music?

You also say "This form is used only to a very limited extent, and then principally in vocal music, the harmonic form being in almost universal use in spite of the augmented second." when speaking of Melodic Minor.

This is totally inaccurate. You really shouldn't put stuff like this in your documents or else people will simply dismiss your information, and assume since you don't know something as rudimentary as this, that all of your other information will likely be faulty (which is why so many Theory websites suck). You really need to understand how scale degrees 6 and 7 were used in minor keys in CPP works to understand this, but to be brief, the so-called harmonic minor scale and melodic minor scale were used with equal frequency in all genres. In fact, the interval of the Augmented 2nd is strenously avoided in most (classical) music, and more especially so in Vocal music because of it's difficulty to sing.

So I'm not trying to pick on you, but I'm really disappointed when I see yet another webdite providing mis-information to people. You really do you and your site a disservice.