Well, it really depends on the level of the rider. Some people pick things up much quicker then others. If you stick too closely to a lesson plan, you may go too fast or too slow for a particular rider. You should instead try to have a series of skills.... and build on them as they are each mastered. For example, my new riders learn things in this order:

Barn/Horse Safety
Catch/Lead
Groom
Tack
Mounting
Body Position (Equitation - proper position and why it is important and how it affects our riding)
Basic Steering/Halting at the walk (discussion of aides, use of leg/seat, pressure, etc.)
Posting (on lunge until they can post without using reins for balance)
Sitting Trot (on lunge until they master without use of hands for balance)
2 point/Jumping position (on lunge until they master without use of hands)
Trotting (Post/Sit/2 point off lunge with ability to have quiet hands/leg/seat)
Ground/trot poles
Canter
Cross rails
Etc. Etc.....