Mythology seems like a good subject choice! Here's one example of a class which has been taught on HOL in the past:
Greek Mythology 101
Here's an example of a year long class, which I updated and brought back:
The Real Tudors
The lengths of the lessons should give you a good idea.
I'll message you.
***edited***
Maybe others are interested, or have more to add, so i'll post what I said,
in general, in my message to Lucia:
Sounds like you've already made a start, which is great! Generally, the deadline for submitting classes for the Fall term will be approximately 20 August, just so you know.
You've:
1) found a subject which appears interesting and you seem to have enough information for a class
2) You've begun writing the class
3) you need a class email address
4) sounds like you've chosen a site to host the class: Google Sites, Weebly, etc.
5) you may have the name for the class
Questions to consider for a 1 year class:
1) do you want 10 lessons?
2) 4 lessons, 1 class project and 1 final, and then 4 more lessons, a 2nd class project, and a 2nd final?
3) would your class be better broken into two different classes? Students are required to take the first class before they take the second class?
4) or would the class work better as 2 separate classes?
Your answer to this will affect how you write your lessons.
That's how, in this case, i would begin.