A lot of people call the major & minor pentatonic scales their "Blues Scale". While this is close to the truth it is not correct. I use to make this same mistake, the scales below are basically your five minor pentatonic scales, but there is an extra note added. It is the same single note but at different octaves throughout each scale. By adding this note each scale will have a more bluesy tone to it when used in a solo.
The grey notes on the scales below show the extra note added to the minor pentatonic scale to make the blues scales. The black notes are the root notes.
Recommended starting positions for the pentatonic scales on your guitar.
|ELECTRIC GUITARS: (cutaway) All patterns will start from these positions if you play this scale in the key of A (5th Fret).
|ACOUSTIC GUITARS: (non cutaway) All patterns will start from these positions if you play this scale in the key of F (1st Fret).
You can use the same formula of scale exercises over the blues scales, ascending and descending in groups of 3 and 4 and so on. After doing the major, minor and pentatonic scales you should have a grasp on what exercises work well over these scales.