Brilliant and well done.
You handle these topics very well. I saw your latest entry on the front page and decided to go through and watch them all. I'm pleased as punch that I did. I don't write reviews very often, and hardly ever sign on. But this deserves praise.
Each video is broken down so well. You have a gift for explaining things. Your animations are cute and interesting to keep attention but also visually helpful to what your saying.
I have to say, some more annunciation would be fantastic. When using a word like "energy" if you don't really keep punching that G the mumbling can get a little bad sometimes. It's understandable though. You are explaining a broad range of things, giving us basics so we can understand and then following through with some hard and interesting facts. You still have a great timing and flow, so I can understand everything you say, and I LOVE the enthusiasm in your voice as well.
You provide some counter arguments. Some would say not enough, but it seems to me that your goal is to explain and educate. You have a good habit of citing sources and resources people can use to broaden their understanding, and finally discover those counter points.
Any educated person knows not to just take something fed to them by one source. Of course there are points that could disprove or bring into argument the facts you point out. But there is SO not enough time to cover it all.
It's amazing enough that you wrap it all up so well in each episode. One point of improvement would be watch out, patch man's lecture poses will eventually get tiresome if repeated so often. He has good variety now but throw in some more of those last minute "mindgasm" motions at the end and i'd be satisfied :)
Overall....
Flash: 10/10
Voice: 8/10
Spirt Science as a series? 10/10
I look forward to following this :D