Publisher link for the whole set, at a discount to boot.
There's something about putting entertainment and education together that seems to boggle the mind. Entertainment is supposed to be fun, and education… isn't. Therefore, "edutainment" is usually seen to be Trying Too Hard, and only the really effective ones survive.
What is effective may be a difficult question to answer. Something that is great for one person may be horrible for another, and so when I say that the Manga Guide books are Effective Teaching Materials, I can only speak for myself.
The books are set at a secondary school level: if you've studied the subject then, you probably already know all of this. In Singapore, secondary school is age 13 to 16 (you start on the year of your 13th birthday, so technically age 12), so I suppose this would be high school in US terms. Most of this stuff will probably be learned in Secondary 3 and 4, at the depth that will generally be taught at that level: you'll be introduced to, say, Newton's Laws, and learn how to apply them in simple situations, but all the little niggly details that tend to trip people up when they revisit the subject at a higher level are brushed aside, because that's not what the books are for.
They also obviously do not teach everything you're supposed to learn at that level. The one for Physics deals mostly with the whole force-and-motion thing, which leaves out stuff like circuitry and electromagnetism and thermodynamics and whatnot. (Presumably the electromagnetism bits will be under The Manga Guide To Electricity, which upon browsing I am sad but unsurprised to note does not include any form or mention of Biri-biri-san.)
For my first round, I got The Manga Guide To Physics and The Manga Guide To Databases. I did study physics in secondary school (didn't do too shabbily then), but it's been over a decade since then. I've never formally studied databases (or at least not databases as is, rather than being attached to MySQL or whatnot), but being Le Geek on the Internet means that I'm largely familiar with the hows and wherefores. So the books did not actually teach me anything new, but they were good refreshers.
And, of course, the manga portions were fun.
Each book is illustrated by a different artist (or set of artist-and-writer). There's the manga sections which deal with some situation arising which requires knowledge of the subject to solve, and there's the big explanatory blocks of text-and-equations after the manga bits which go further into the concept. The manga is read left-to-right, which caused me a small amount of difficulty at first.
MGTPhysics deals with one Megumi Ninomiya, who is not very good with the subject in question, and her role as Simplicio is further reinforced in my mind by her mild resemblance to Yui Hirasawa. Megumi has been beaten in tennis by Sayaka, who is pretty much the ojou-sama tsundere archetype, due (somehow; it's presented as "it bothered me during the match, so I couldn't concentrate") to the counter-intuitive nature of Newton's Third Law (the one about equal and opposite reactions). So she enlists the help of her classmate, "International Physics Olympics Silver Medallist" Ryota Nonomura, to figure out the mysteries of Physics. It's done in a school-life slice-of-life kind of way, with Megumi occasionally flirting with Ryota, presumably just to break up the tension and Walls of Text.
Meanwhile, MGTDatabases is set in the Kingdom of Kod (somehow), a fantasy kingdom deriving its revenue from sales of fruit (somehow), and Princess Ruruna and her personal assistant Cain are visited by the Database Fairy Tico to help them organize their kingdom's fruit sales. Somehow. It gets a little odd, with various NPCs dressed in medieval court clothing typing away at modern computers. There's also Prince Raminess from a neighbouring kingdom, who is FABULOUS enough to probably be voiced by Daisuke Ono. It's a more shoujo art style than MGTPhysics.
The MGT books are probably not the most efficient way to present information, but by going back to the dialogue method of instruction and adding the familiar anime-esque style of humour, it's a lot less dry than a textbook, at the trade-off of taking up more pages to explain stuff. This is perfect for revision, rather than teaching; the books appear to be for reading on your own, and maybe asking a friend for help if you get stuck, but in a classroom it's basically the teacher's job to do what the manga sections are doing: give examples and explain the concepts in a more interesting manner. (The fact that this does not happen very often is kind of sad.)
Should you get it? If you are taking the subject at that level right now, certainly. If you want to brush up, it's great. If you already know all of this, though, then the only appeal will likely be the manga sections, which are good for a few minutes of entertainment, but probably not worth the price.
Personally I'm happy with these because I have learned that when writing fiction, you never turn down knowledge of any sort, and revising always helps. Also, I am an inveterate fanfiction writer, meaning that already I am speculating on the possibilities in the characters.