MVP's for Content-Based Startups?

Hi all,

I've gotten an idea for a product, but it is content-based. It's a learning platform, where I'll teach courses on programming.

The main concept is courses consisting of a list of ultra short lessons (5 to 8 minutes) followed by one or more practice assignments. The idea is to let people learn at their own pace, with the possibility of having meaningful progress in about 15 minutes per day.

How would I go about making an MVP for this? I've so far had the following ideas:

1. Make the site, let people sign-up for courses, so they'll be notified on release. (no pre-pay)
2. Create a single course, with all lessons and practice assignments, then sell that.
3. Start creating course, release lessons as they are finished, but discount the course for as long as it is unfinished.

I feel number 1 is the better option, as it means I can validate the demand in time. Number 3 is also pretty good, as I can measure demand more directly, by seeing if people are actually willing to pay for this.

What would you do?