For Guardians

1The Guardian Is the Contracting Party

The service is offered to residents of Japan. The contracting party is one adult who is the child’s parent with parental authority, guardian of a minor, or other statutory legal representative under Japanese law.

This English text is provided for reference only. The Japanese version is the authoritative text and prevails in the event of any discrepancy.

The child uses the service but is not a party to the contract. Only the contracting guardian can make payments, change plans, cancel, change registration details, or delete the account. One account may register one child.

The child learns using the contracting guardian’s account; there is no separate login for the child. Management of the account, the device, and the payment method is the contracting guardian’s responsibility.

This page does not set out contractual rights and obligations. Those are set out in the Terms of Use, the Privacy Policy, and the Children’s Privacy Notice, which prevail where the content differs.

2Guardians Other Than the Contracting Guardian

Guardians other than the contracting guardian are welcome to look at how the child is learning, by having the contracting guardian show the screen. Please do not share credentials (email address and password).

Such guardians have no authority to contract, pay, cancel, change registration details, or delete the account.

Where such a guardian wishes to make a request such as disclosure or deletion, the operator responds after confirming statutory representative authority or other legitimate authority. Watching over the child’s learning does not by itself confer authority to change the contract or the account.

3Fees and Auto-Renewal

Fees are JPY 1,200 per month or JPY 8,000 per year, both tax included. The amount displayed is the total amount payable. There is no free trial and no free learning plan.

The contract is formed at the point the payment for the subscription succeeds. Paid plans auto-renew. If you do not wish to continue, complete the cancellation procedure before the next renewal date. After cancelling, you can continue to use the service until the last day of the contract period already paid for.

Deleting the app, logging out, or clearing browser data does not cancel the subscription. Cancellation and account deletion are also separate procedures. The cancellation procedure, the treatment of failed payments, and the refund conditions are set out in the Subscription and Refund Policy.

4About Your Child’s Information

The service handles the nickname, school year, and learning records, to the extent necessary for learning. Unless necessary, the operator does not ask for the child’s real name, address, telephone number, or school name.

The child is the "principal" under the Act on the Protection of Personal Information with respect to their own information. Requests such as disclosure, correction, or deletion are in principle accepted from the contracting guardian.

Where the operator asks to interview a child, it requires the contracting guardian’s individual consent and presence. Participation is voluntary and is not a condition of using the service.

For details, please see the Privacy Policy and the Children’s Privacy Notice.

5Worth Conveying to Your Child

We suggest conveying the following three points, in a manner suited to your child’s level of understanding.

• That a record of the problems they solve stays in the app
• That the guardian can also see those records
• That they may talk to their guardian if something troubles them

6How We Think About the Service

The service is not a tool for competing over test scores or rankings. Through arithmetic practice, it aims to develop the ability to keep going, to come back after a day that did not go well, and to take on difficult problems.

For that reason, the service is designed as follows.

• We do not display comparisons with other children. The comparison is always with the child’s own past.
• We do not point out drops in accuracy or periods without learning in a way that is visible to the child.
• We do not use points, rankings, or other external rewards to keep the child learning.
• We do not use language that demands the next action — such as "let’s do our best again tomorrow" — in messages to the child, result screens, notifications, or reports.
• We do display guides for learning volume (daily and monthly goals) on the child’s screen. They are calculated at a pace that can be reached even with five days off per month, and are shown in two tiers: a minimum guide and a challenge guide. Days that fall short are not displayed in a way that blames the child.

7Suggestions for Home

• Rather than scores or accuracy, speak to the fact that they worked on it, that it is continuing, and that they chose a difficult problem.
• Judge continuity by the week, not by the day. A few days’ gap is fine if the week as a whole continued.
• On a day when your child resumes after a break, acknowledge the return itself rather than the results.
• If it looks like too much, it is fine to reduce the number or length of learning sessions.
• Explain the three points above, in a manner suited to your child’s level of understanding.

8Please Confirm Before Subscribing

• The content of the Terms of Use, the Privacy Policy, the Children’s Privacy Notice, and the Subscription and Refund Policy
• That the contracting party is one adult statutory legal representative, and that the child is not a party to the contract
• That the child learns using the contracting guardian’s account, and that credentials are not shared
• The fees (JPY 1,200 per month / JPY 8,000 per year, both tax included) and that there is no free trial
• That the plan auto-renews, and the deadline and method for cancellation
• That the contracting guardian is responsible for managing the account, the device, and the payment method