Reduction 1000
An arithmetic improvement app, conceived by a University of Tokyo graduate

The First Hurdle: Reduction

According to the 'Survey on the Mathematical Ability of Elementary School Students', the accuracy rate for decimal and fraction calculations is low, and there are many cases where the result of fraction calculation is not reduced.
In mathematics after junior high school, you are often asked to give the answer in the form of a fraction, and if you can't reduce it properly, you will lose points.
It is very important to learn to reduce properly at the elementary school stage for future arithmetic and mathematics learning.

The Strength of Reduction 1000

According to developmental psychologist Professor Naoko Itoi, 'fractions are one of the most difficult areas to understand in elementary school arithmetic.'
Ideally, you should first understand the meaning of fractions, then learn how to calculate them, but the concept of fractions is complex and it's not that easy.
So, you might want to deepen your understanding of fractions by solving problems over and over again like muscle training, but don't you get bored and tired of solving commercially available calculation drills?
Reduction 1000 has the following strengths to solve such problems!
  • You can play easily on a PC or smartphone for free
  • There are sound effects and effects, so you won't get bored
  • The tempo is good and you can progress crisply
  • Automatically scores for you
  • If you make a mistake, it will tell you not only the answer but also the calculation process
  • You can save the result as an image with one button
Play video

Rejoice together

As far as I know, there were few students of University of Tokyo, most prestigious institution of higher education in Japan, whose parents forced them to study, and there were few who were left alone.
So, what were the parents of these students doing?
It seems that they were rejoicing with their children.
It is easy to imagine that if you force your child to study, they will hate studying, but on the other hand, if you praise them, being praised will become the purpose and they will not study on their own.
Therefore, by rejoicing with the child, you can nurture autonomy while staying close to the child.

Reduction 1000 has a function that allows you to save the result as an image by pressing the camera button.
Let's share the joy together and enjoy the fun of arithmetic.

You can get a trophy if you score more than 90 points

Play Reduction 1000

Reduction 1000

The path to a reduction master, start with 1000 questions!
Improve your calculation skills quickly with a game-like experience.

App Browser Education


  • 八木義弘「小学生の計算力に関する実態調査―全体の傾向について」
  • 糸井尚子(2008)『子どもは小さな数学者』