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High School English App

Zero frustration.
Master high school English.

Kokoei is an English learning app designed for Japanese high school students (Grades 1-3). Master grammar and vocabulary with clear Japanese explanations and diverse quizzes.

Features

6 Key Strengths

Understand the "why" behind English grammar and turn it into your strongest subject.

Structured Curriculum

3 courses covering Grades 1-3, with 41 units total. From sentence patterns to the subjunctive mood, the entire high school English curriculum is systematically organized.

Clear Japanese Explanations

Complex grammar terms are broken down in plain Japanese. Every English sentence comes with a Japanese translation and visual diagrams for intuitive understanding.

Common Mistake Prevention

Compare "wrong examples" with "correct examples" for points where students commonly stumble. Prevent test deductions before they happen.

Diverse Quiz Formats

Multiple choice, fill-in-the-blank, true/false, word ordering, and translation questions. Every question comes with a detailed explanation.

AI Learning Assistant

Ask questions during lessons and get instant help from AI. It can also generate custom quizzes based on the lesson content you've been studying.

Smart Review Mode

Analyzes your learning data to automatically detect weak areas. Uses spaced repetition to suggest review at the optimal timing for lasting retention.

Curriculum

Curriculum

Three courses designed to progressively build English skills from Grade 1 through Grade 3.

Grade 1 English

Review middle school English and build a solid foundation for high school studies. 14 units.

Unit 01
Foundations of High School English
4 lessons
Unit 02
Basic Tenses
3 lessons
Unit 03
Auxiliary Verbs
3 lessons
Unit 04
Passive Voice
3 lessons
Unit 05
Infinitives
3 lessons
Unit 06
Gerunds
3 lessons
Unit 07
Participles
3 lessons
Unit 08
Relative Pronouns
3 lessons
Unit 09
Relative Adverbs
3 lessons
Unit 10
Comparison
3 lessons
Unit 11
Subjunctive Mood
3 lessons
Unit 12
Vocabulary Building
3 lessons
Unit 13
Idioms
3 lessons
Unit 14
Introduction to Reading
3 lessons

Grade 2 English

Build on Grade 1 foundations with advanced grammar and practical English skills. 14 units.

Unit 01
Sequence of Tenses & Perfect Tenses
3 lessons
Unit 02
Advanced Auxiliary Verbs
3 lessons
Unit 03
Causative & Perception Verbs
3 lessons
Unit 04
Advanced Infinitives
3 lessons
Unit 05
Advanced Gerunds
3 lessons
Unit 06
Participle Constructions
3 lessons
Unit 07
Advanced Relative Clauses
3 lessons
Unit 08
Conjunctions & Clauses
3 lessons
Unit 09
Advanced Comparison
3 lessons
Unit 10
Advanced Subjunctive Mood
3 lessons
Unit 11
Negation, Emphasis & Inversion
3 lessons
Unit 12
Reported Speech & Substitution
3 lessons
Unit 13
Nouns, Articles & Pronouns
3 lessons
Unit 14
Adjectives, Adverbs & Prepositions
3 lessons

Grade 3 English

Integrate all knowledge for university entrance exam preparation. 13 units.

Unit 01
Comprehensive Grammar Review
3 lessons
Unit 02
Collocations & Sentence Patterns
3 lessons
Unit 03
English Interpretation Techniques
3 lessons
Unit 04
Japanese-to-English Translation
3 lessons
Unit 05
Free English Composition
3 lessons
Unit 06
Long Passage Reading
3 lessons
Unit 07
Listening Comprehension
3 lessons
Unit 08
Common Test Preparation
3 lessons
Unit 09
Private University Prep
3 lessons
Unit 10
National University Prep
3 lessons
Unit 11
Thematic Vocabulary
3 lessons
Unit 12
Background Knowledge
3 lessons
Unit 13
Comprehensive Practice
3 lessons
How to Use

How to Use

Start learning in 4 simple steps.

1

Choose Your Course

Select the course matching your grade level (Grade 1, 2, or 3). If you want to review from the basics, start with Grade 1, Unit 1.

2

Study the Lessons

Each unit contains multiple lessons. Follow the flow: grammar point, examples, common mistakes, then summary. Everything is carefully explained in Japanese.

3

Take the Quiz

At the end of each lesson, check your understanding with a quiz. Multiple choice, fill-in-the-blank, word ordering, and more. Wrong answers come with detailed explanations.

4

Review & Retain

Smart Review mode analyzes your learning data and suggests optimal review timing. Focus on weak areas with targeted training for lasting retention.

FAQ

Frequently Asked Questions

Common questions about Kokoei.

Kokoei is an English learning app designed for Japanese high school students in Grades 1-3. The name comes from "Koko" (high school) + "Ei" (English). It helps you master English grammar and vocabulary with clear Japanese explanations and diverse quiz formats. It's also useful for regular exam preparation and university entrance exam preparation.
Please check the app store listing for pricing details. Some content is available for free.
Yes. Learning content is stored within the app, so you can access lessons and quizzes without an internet connection. The AI features require an internet connection to use.
Absolutely. The first unit of the Grade 1 course, "Foundations of High School English," starts with a comprehensive review of middle school English. With careful explanations from the basics, even students who struggle with English can start with confidence.
Yes. Lesson progress, quiz scores, and streak days are all saved on your device. Even after closing the app, you can resume learning right where you left off.
It's a feature that lets you ask questions to an AI during lessons when you don't understand something. It can also automatically generate original quizzes based on the lesson content you've been studying. Available formats include multiple choice, true/false, fill-in-the-blank, and mixed questions.
Yes. It's also recommended for adults who want to relearn high school English. With careful Japanese explanations and progressive difficulty, you can learn from the basics at your own pace.
Contact

Contact Us

Feel free to reach out with questions or feedback.

Contact by Email

Questions about how to use the app, bug reports, feature requests — we'd love to hear from you.

eerf0309+kokoei@gmail.com