Suggestion: Add "In Progress" to lesson dropdown selections

I love that I can mark a lesson as Bookmarked/Studied, etc., but what about that lesson that I start, and can't finish all in one sitting... like I've done everything except The Fix.... or I want to come back later and review everything once more before I mark it Studied... or what if I'm a multi-tasker, and have several going at once.

 It would be great to have an "In Progress" dropdown choice so that I can easily keep tabs on such lessons.

You guys rock!