Kit 2: Spy Set

Kit #2: Spy Set (1680 yen). This is probably the weakest kit in the series, but has the most hard-science filled mook that I’ve seen so far. Technically, this is really a forensics kit, containing a polarized LED (the battery that comes with it is dead, though), fingerprint powder, and a couple small bottles of chemicals for identifying blood and other simple substances. The mook starts out with a murder mystery using the products in the kit to help solve the case. The bottles are small, and there’s not a lot of reason to go around fingerprinting random stuff (I also don’t have a big need for trying to find blood in the living room). Even if I did use the kit, the chemicals would run out quickly. So, in this sense, the kit has little more than a minor collector’s value. Even so, there is a small amount of building to be done, in order to assemble the holder case (about 15 seconds worth).

The mook is the more impressive part. While it starts out with the murder mystery, it then goes into the actual science behind forensics, and how luminal works to make blood fluoresce under black light. There’s also a section on low-cost DIY projects, such as how to make an arc lamp using a pencil lead, a Stirling engine with a piece of paper and two glasses of water, and how to use a rubber eraser to make copies of photos. There’s a good section on how to collect various Japanese insects, an article on a man that makes musical instruments from straws, and a pair of 3-D glasses for looking at 3-D photos in the mook.

If you like the CSI TV shows, you’ll like this kit. If you like building inexpensive science projects, you’ll love this mook. It helps being able to read Japanese, but there’s so many pictures and illustrations that the text almost becomes unnecessary. But, if you want to buy this kit to have something to assemble and play with afterward, you’ll be disappointed.

Kit 1: Putt-Putt Boat

I have a blog over at ThreeStepsOverJapan (TSOJ), where I ran my original reviews of the Gakken kits. I figure that now I’m starting up this dedicated blog that I might as well reprint the earlier reviews. Please note that when I started out, in the middle of the kit series, I wasn’t reviewing them so much as just documenting what the finished product looked like, so the entries are short and perfunctory. Sorry about that. Additionally, I don’t want to pay the mark-up to get the out-print kits from auction sites, so there aren’t any reviews of kits 3, 4, 5, 7 and 12 right now.

I am cleaning up the reviews and breaking them into single-kit entries for those which were written as 2 kits per post. In some cases, I had follow-up posts for mods or additional information that I may recombine into one big entry for the kit. So, these following posts aren’t going to be word-for-word clones of the TSOJ entries.


Gakken is a publisher of textbooks and DIY magazine books (AKA: mooks). There are currently 32 “Adult Scence Kit Mooks” on the market, from simple guitars and crystal radios, to theremins and a build-it-yourself film projector. Most mooks in this series are in the $35 to $50 range now. Originally, they had a 4-kits-per-year release schedule, but now it’s getting closer to 2 a year for the numbered series. There are several other unofficial series, such as Mechamo, With Kids, unnumbered mooks, higher-end kits without mooks, and the new Sound Gadget series. There’s also the mook-without-a-kit, including the “history of rockets” book and the Theo Jansen DVD book. For the most part, I focus on the numbered mook kits, because they’re inexpensive, yet fun to build.

Kit #1, the Putt Putt Boat. These kinds of boats have been around for years, and there are a number of vids on Youtube showing how to make your own out of plastic soda bottles or sheets of tin. So, it’s not like Gakken is giving us anything really new here in the very first kit from this series. It’s also a fairly simple kit, with a one-piece plastic body for the boat, 3 pontoons, a candle tray, holder and 4 candles, and the steam chamber. The science behind this kind of boat is very straight-forward. A small amount of water is placed in one tube of the engine to prime it, and then a candle is lit and placed under the steam chamber. Steam builds up in the chamber and the pressure expels it out the other tube, pushing the boat forward. More water flows into the chamber from the primed tube and the process repeats until the candle burns out. As long as the boat is in the water, it creates a closed circuit for the water flow.

The problem is that this kind of boat isn’t designed for being used outdoors. I tried launching it from the nearby river, and the couple-mile-an-hour wind put out the candle, and the 1-2 inch tall waves swamped the boat and soaked the wick. At best, I need a perfectly calm day, or to use an indoor pool or bath tub. The candle is tiny, so it’ll only burn for a few minutes, too. Which makes it kind of silly to have a small hole in one fin of the boat for tying a thread to it for hauling the boat back if it gets too far out from shore. It may be possible to use a slightly larger candle, though, to make it run longer (the size of the engine limits how big a candle you can use). The mook suggests taking foil to make a tray, pour in salt, add whiskey and then light the whiskey. But the wind again blew out the flame. I’m wondering what would have happened if I had used sugar instead of salt.

But, the real value from this kit is in the mook. Published in 2003, it is interesting on multiple levels. First, it’s the first of the series, and shows how Gakken initially thought the series would run (mostly by including ideas for cheap DIY science projects). Second, it contains a photographic history of 40 years of science toys for kids, most or all of which had come from Gakken. Third, this mook is a treasure trove of mods for other Gakken Adult Science kits, including the Edison speaker amp, and has a circuit for the 150 block electronics kit to make a theremin. Finally, there’s a series of science experiments for performing magic and bar tricks, such as smoke from your fingertips, and how to make a ping pong ball stick to the bottom of a bottle of water. And, I did translate the manga at the back, showing the rivalry between Edison and the inventor of the first flat-disk record player, Emile Berliner.


I decided to go back and look at the various Gakken Otona no Kagaku mooks more closely to see what I might have missed the first few times through them. One of the more egregious oversights regarded a group of people that were featured in Vol. 1 of the series. This group had been interviewed on their favorite science kits from when they were kids. Of the 7 primary people, 6 had URLs given for them (the seventh is a writer that shows up in all of the subsequent mooks). Of the 6, Iwai is the only one “left without a forwarding address”. Tosa is president of Maywa Denki; Furuta is at the University of Chiba doing some cool stuff with robotics, and Sakana-kun is just a wild and crazy fish boy with his own children’s show. Check them out.

Maywa Denki
An Art Project Company
Featured Person: Nobumichi Tosa
(I like the “nervous knee” electrical generator toy.)

Institute of Advanced Media Arts and Sciences
Featured Person: (Iwai, Missing)

Japan Science and Technology Agency
Chiba Institute of Technology
Featured Person: Furuta Takayuki
(Got some great articles on robots, and videos of wind-up toys)

Artist – Anime, Manga and Other
Featured Person: Tanaka Katsuki
(Interesting Website)

Osaka University
Department of Multimedia Engineering
Featured Person: Tsukamoto Masahiko
(Cool gadgets)

Art and Other, Children’s Entertainer
Featured Person: Sakanakun
Looks like Sakana-kun has his own children’s show. Weird stuff.

Gennai Hiraga in popular media

It’s strange when two or more interests converge unexpectedly. In my case, this time, it’s manga and Gakken kits. I like reading different kinds of stories, and one that I’ve just started following is Kurogane, which is set during the Edo era (1600-1700’s). The other is the Gennai Hiraga (1728-1780) “static electricity kit“.

At the very beginning of the Kurogane story, the hero is in the home of Genkichi (源吉), an inventor possibly based on Gennai (源内). Check out the bottom right corner panel.

Just for reference, “Gen” is “source of”. “Kichi” is “good luck”. “Nai” is “inside”. So, “Source of good luck” compared to “Inner source”.

More about the Denshi mini Block

Ok, I mentioned the Denshi mini Block kit before (“Denshi” = “electronics”). I’ve already written up the English translations of the circuit names, with short descriptions of each. There are 50 circuits given in the mook that can be made using one kit. Another 6 experiments are offered if you have two kits, giving you an incentive to talk your friends into buying their own kits.

The Gakken site has several links that are easy to overlook (the pages aren’t in English, unfortunately).
Main kit page
List of circuits
List of blocks
Articles in the mook
Assembly instructions (PDF)

Now, one link that’s easy to miss is for the “Playing with kit #32” index page. This lets you look at the assembly instructions for 3 of the projects shown in the mook: Julie Watai’s fluffy pink rabbit; the synth and sequencer project; and Schrodinger Cat circuit (make your own Geiger counter and use it to see if the cat is alive or not). A lot of soldering of new circuits required for each project.

Gakken also likes circuits that use the Japanino:
Japanino-driven LED meter
Japanino-driven radio On/Off circuit

This finally brings me to the 6-page Background Series for kit #32.
Description of the EX-150
Talking about how the Denshi mini was designed
Making the individual blocks
Deciding on the blocks for the radio circuit
Finalized design and sample circuits
Electronic Bird Chirper

This last page, the bird chirper, gives you Circuit #51. It uses the Railroad Signal Blinker from the mook, but disconnects the oscillator Vcc line from the batteries. You use the jumper paddles to add body resistance in powering the oscillator. I found that using this approach doesn’t work for me. I had to connect the two paddles directly. The frequency and sharpness of the “chirping” is controlled by the IC amp volume control. And the LEDs flash at the same rate as the chirping (i.e. – fast). It’s a nice variation on the blinker circuit.

iPad EX-150 app

Ok, just for fun, I’ll mention this next item, but there may be restrictions on your being able to do anything with it.

(Image copyrights owned by Gakken. Click on image to visit Gakken site.)

Gakken has an iPad app in the iTunes store for emulating the Denshi mini Block kit.

Details on the Otona no Kagaku official Gakken support page.

Outguessing the Otona no Kagaku website

In a way, the Gakken Otona no Kagaku site has a wealth of information while also suffering from a dearth of the same. If you have the kits, the website adds some new information, suggestions for making new mods, and in the case of the synthesizers, videos demonstrating new sounds you can make. Conversely, if you don’t have a specific kit, the website doesn’t give you anything to work with. That is, there’s no online version of the mooks (you’re supposed to buy the kits to get the paper version), and you can’t make any of the suggested experiments if you don’t have the hardware. In this sense, the website is just a teaser to get you to fork out for the kit.

If you plan on buying any given kit, then the website lets you know what you’re getting, when and for how much. You don’t necessarily need to know Japanese, either, because a number of the pages for about half of the kits are in English. The downside, though, is that it may take a few months for the latest kit page to be translated.

If you are an experimenter, then you’ve already tried clicking on all of the links in the Otona no Kagaku site to see what will happen. This tells you what pages are there, but that doesn’t address HOW to read them, if they are in Japanese. Maybe the one page that’s the most useful for non-Japanese is “Next Up”, because we want to know what the next kit will be, when and for how much. It also gives you bragging rights if you can scoop your friends right after new announcements are made on the Gakken site. I wrote a blog entry on hacking the Japanese page. I’ll reprint it here.


If you’re a fan of Gakken’s kits, then you probably visit their website from time to time to see what’s going to be coming out next. And, if you like puzzles, you may even try “hacking” the language. If so (or only if you want to be able to understand what the “probable release date” part means), I’m here to help.

First, Japanese is made up of three alphabets: hiragana, katakana and kanji. Hiragana (written as ひらがな) is a cursive 40-character phonetic letterset that spells out the pronunciation of the word. It is used for normal everyday spelling, and for the tense forms of verbs. Katakana (written as カタカナ) is a rectilinear 40-character phonetic letterset that duplicates hiragana. Katakana is used primarily for representing foreign words and for emphasis (kind of like italics). Kanji is the pictograph set that came from China (written as 漢字). If you want full Japanese proficiency, you need to know just under 2000 characters plus their more common combinations.

Each kanji character can have two or more pronunciations, depending on the word and if it is by itself or combined with another character to form a more complex word. These pronunciations are called Kun’yomi (Japanese reading, by itself) and On’yomi (Chinese reading, when combined with another character). As an example “食べる” is “taberu”, “to eat”. “事” is “koto”, “thing”. When combined, “taberu” uses its on’yomi reading of “shoku” and “koto” uses its on’yomi reading of “ji” to form “食事” – “shokuji”, or “meal”. Ok, time to start.

Please refer to the below screen cap:
At the top left of the index page we have “大人の科学.net”, pronounced “Otona no Kagaku”, meaning “Adult’s Science”.

Underneath this in the index section is “大人の科学マガジン vol. 28”. This is just a repetition of “Otona no Kagaku” with the addition of “magajin”, or magazine. This is the link to the most recently released kit, which in this case is #28, the Edo Clock.

The next entry in the index on the left is “大人の科学マガジン 次号予告”. Again, we have “Otona no Kagaku Magajin” but with “jigou yokoku” – “next issue notice”. This is the link for the next issue in the series, and is the one we want for our purposes (issue #29).

The third item is “大人の科学マガジン別冊”, the “Adult Science Bessatsu (special issue)”. This links to the special kits that include a mook but don’t have issue numbers. The current special issue is the vacuum tube AM radio kit. (真空管工作 – “shinkuukan kousaku”).

The fourth item is another “bessatsu”. This one is the “シンサセイザークロニクル” (shinsaseiza- kuronikuru – synthesizer chronicle).

The fifth item is yet another “bessatsu” – the “ロケットと宇宙開発” (rokketo to uchuu kaihatsu – “rocket and space development”) magazine.

The sixth item may be of some interest to people still relatively new to Gakken kits. This is the “ラインナップ一覧” (rain’nappu ichiran – “lineup listing”). This links to the full listing of all of the Gakken mook kits in the series.


Ok. Click on 大人の科学マガジン 次号予告. This takes you to the page for the kit to come out next. On the right side in the bottom corner is the “electronic guy” and the words “Japanino連動用コネクタつき” No points for guessing that this means “Has a connector to interface with the Japanino” (read as “Japanino rendou you konekuta tsuki”).

Then in the bottom left we have the following:
A4変型判 (A4 henkei ban) – a4 paper size (8″x12″)

100ページ (100 peeji) – 100 pages

2010年11月上旬発売予定 (2010 nen 11 gatsu joujun hatsubai yotei)

It’s this last line that needs explanation. Obviously, we’re being given the date Nov. 2010. “上旬” (joujun) refers to the first 10 days of the month. “下旬” (gejun) is the last 10 days. “中旬” (chuujun) is the middle 10 days (or the middle third of the month). This is followed by “発売” (hatsubai) – “to go on sale” – and “予定” (yotei) – “plan”. Put it all together and you get “Planned released for the first 10 days of Nov., 2010.”

予価: 2,800円(税別) (yoka: 2,800 yen (zeibetsu)) – Planned price: 2,800 yen (not including tax)

ふろく:AKARI切り紙 (furoku: AKARI kirikami) – Make: Light Cut Paper

“AKARI” is the name of the kit, but it translates to “light” or “glow”. “kirikami” is a variation on “origami”, the art of paper folding. Here, kirikami is the process of making shapes that not only includes folding paper, but also modifying it with a knife or scissors (“kiru” meaning “to cut”). More correctly, it’s – “Kit Name: Paper Lamp”.

講入方法: 全国書店 (kounyuu houhou: zenkoku shoten) – Purchase Information: All stores countrywide. More correctly, this would be – “Available in bookstores everywhere.”

学研オンラインショップ: 『ショップ.学研』 (gakken onrainshoppu: “shoppu.gakken”) – Gakken Online Shop: “shop.gakken”.


And there you have it. On Page 1 on the left from the top:

Adult Science Magazine vol. 28
Adult Science Magazine Next Up
Adult Science Magazine Special – Vacuum Tube Radio
Adult Science Magazine Special – Synthesizer
Adult Science Magazine Special – Rocket and Space
Adult Science Magazine Product Line Up

On Page 2:

Includes connector for interfacing with the Japanino

Magazine size: A4 / 100 pages / Tentative release in first week of Nov. 2010
Suggested Price: 2,800 (without tax)
Name: AKARI Paper Lamp
Available: Bookstores nationwide
Gakken Online Shop – “shop.gakken”

It’s just that easy. Next up, how to safely remove your own spleen with just a spork and two hedgehogs.

Otona no Kagaku email newsletter

I was hoping for a little more response, but thanks for the one feedback. I will keep using this blog for announcing news and reviews for the Gakken kits.

I’ll start things off by mentioning the Gakken email newsletter (AKA: the “electric magazine”). You can sign up for it from the Otona no Kagaku page, but it’s only in Japanese. I haven’t really seen a pattern to when it comes out. I think the last issue was #149 (I didn’t keep it so I can’t go back to look). Generally, it seems to be mailed just before or after some major event.

The latest issue advertised some videos showing how to generate new sounds from the SX-150 Mark II synthesizer, with a mention that there’s still plans for releasing the Udar under the Sound Gadget Series blanket in the near future.

I don’t remember if the following item was mentioned in the newsletter or not, but the Otona no Kagaku site also has a new article on a circuit you can make with the Denshi mini Block kit that wasn’t included in the 50 circuits in the mook. It’s titled “little electric bird. Basically, it’s the railroad blinker circuit, but you connect the oscillator Vcc pin to the battery by touching the two jumper paddles with your fingers to add variable resistance.

The newsletter also reports on the live “Denshi mini Event” that had been held in the middle of December. The event allowed the public to meet the kit designer, watch presentations on how electronics works, and to play with the mini block kit prior to buying it. There was also a Q&A feedback session. The newsletter recapped some of the feedback. Apparently, the event was attended by a number of individual housewives, families and unattended kids, surprising the organizers by the diversity of its market. While the kit is good for parents wanting to teach kids about electronics, the main complaints revolved around parts breaking, and the difficulty of buying blanks in bulk for making your own blocks. Gakken promises to address these issues in the future.

The newsletter wrapped up with the announcement of the target release date for kit #33. This is the vacuum cleaning robot. The article asks “how can a small vacuum cleaning robot accurately cover the top of a desk without having an electronic controller, and being mechanically-driven only?” Expect it to come out around Jan. 30, 2012. No official price yet.

Requests for feedback

I know that very few people know that this blog is here, but because you’re being redirected from the knol pages to the annotatum articles on WordPress, there’s a chance that some of you may see this entry and actually read it.

First – I hate annotatum.  It’s one of the hardest interfaces I’ve ever seen for writing articles, and it’s pretty much destroyed everything I’ve tried to edit or create from scratch (the import feature from knol to annotatum works fine, as long as I don’t touch the article ever again after the import).  So, I’m moving my articles over to

Second – WordPress itself seems to be ok.  I may keep this blog.  If I do, I’ll probably dedicate it to the Gakken Otona no Kagaku kits.  I’d just like to get your feedback on this.  Do you like the Gakken kits, and do you think having a blog dedicated to them would bring you back here regularly to see the updates? (Keeping in mind that updates may be only every 2-3 weeks.)


Welcome to TSOJ ver. WP

Hi.  It seems that Google is phasing out their “knol” system, and replacing it with something new based on this WordPress blogging system.  Because I already have a blog on Goggle’s blogspot, having to come over here and set up one on WP as well seems a little silly.  So, I’m going to keep my original blogspot account, and just use WP here for holding my existing knols.

About me – I’ve lived in Japan for a while now, and my interests pretty much run the gamut from anime and manga, to sightseeing in Japan, cycling, hiking, and building electronics kits.  The bulk of my knols have revolved around Gakken’s Otona no Kagaku (Adult Science) series, with some spring boarding to the Japanino (Gakken’s version of the Arduino hobbyist micro-controller).   Feel free to browse around and let me know what you think.