ブーハー・アドベンチャーへようこそ

This is The Booha Adventure, and it connects to the world of my novel Karasuki. Once you enter, you can review, listen, and practice all the weekly content without going any further. There are three curricula to choose from.

This app isn't connected to AI or any external API. Everything is local. Everything you read, see, and hear lives inside the app. From the study deck page, you can even chat with Uhibon. He knows everything about the app—and nothing about anything else. LOL.

I designed this app to be explored and to get lost in. The further you go, the more you find. Click the maze and you'll see the Booha Ghost flying around. One of them will meet you at the start and guide you to this week's games. Each curriculum has its own set of 9 games and its own theme. The more you play, the more unlocks in Karasuki. That's all I'm going to say.

Play a game and travel to the Karasuki tree. Remember—most trees are doorways to something.

You'll find your Adventure Profile page in Karasuki. Only you can see it. No one else—not even me—can see your progress or scores. You're in charge of your motivation and your output.

Curriculum guide

Curriculum	Eiken Level
Pre-Boo	Around Grade 5–4
Boo-riculum	Grade 4–2
Boo-Continuum	Grade 2 and above

I built this app for my output-based school. Output is the language you produce—not what you read aloud or memorize, but what you actually use to communicate. Most students use Boo-riculum. All curricula overlap, so they can be combined. They loop and build practical conversational English without locking you into a fixed level. Your level is based on how much you use the language.

Each curriculum shows three weeks of study decks at a time: this week, last week, and next week. Each week includes 15 vocabulary words, 15 sentences, and 15 questions, all with full audio and Japanese translations, plus a hands-free stream for listening and repeating.

Nothing is recorded outside your device. Your data belongs to you.

The Booha Adventure was built for my school and is included with lessons. Other schools are welcome to use it. I offer a two-week free trial.

PINs	Price
1 PIN	¥500
10 PINs	¥5,000
20 PINs	¥9,000
50 PINs	¥50,000

We do not write during lessons. Writing happens at home so class time can be used for speaking and real communication. Every student keeps a diary. Each week, write the weekly vocabulary in English and Japanese and bring it to class.

Study Decks The study decks are the foundation of everything. Nothing else works properly without them. Every week includes vocabulary cards, sentence cards, and question cards, all with full audio, along with a hands-free stream for listening and repeating.

The vocabulary cards train your ear and eyes to recognize the week's core words quickly. The sentence cards show how those words live inside real English. The question cards prepare you to respond, not just understand, so when it's time to speak you're not starting from zero.

The hands-free stream is where everything connects. You listen, repeat, and move with the language without stopping. This is where rhythm, confidence, and flow build.

These decks are not something you finish once. Come back to them until the English feels familiar.

Game Decks Each week includes 9 games built around the same English you studied.

The games are not separate from the study. They are where you use it. When the study decks feel familiar, the games feel smooth. When you skip the decks, the games feel hard. The system is honest like that.

As you complete games, more things begin to appear and unlock across the Adventure. The more you play, the more the world responds.