The Asian Development Bank (ADB) and the International Initiative for Impact Evaluation (3ie) have published a set of six video lectures on impact evaluation. They are available here. The lectures are presented by different specialists; the slides accompanying the lectures can be downloaded from the same website.
I have taken a look at Dr. Jyotsna Puri's lecture on quasi-experimental methods. Dr. Puri illustrates the use of such methods with a real example she has worked on. The lecture is quite clear, but be prepared for technical jargon and high information density. Also, a basic understanding of mathematics helps - you need to know where to find the x axis and the y axis on a graph. This is not for absolute beginners, but arguably, impact evaluation, in particular the kind of rigorous evaluation 3ie promotes, is not for beginners (nor for the financially meek, by the way).
A nice feature is the quiz that one can take after each lecture. What I like less about it is that you need to log in to take the quiz - what for, I wonder? There are no prizes to gain or diploma to obtain. Only the user's privacy to lose. In my view, that is an unnecessary hurdle which might put off some prospective learners.