Hi there! I’m sorry to hear that LetterSchool crashes when you enter the Japanese language sections. To help you better, could you tell me a bit more about when exactly it crashes? For example, does it crash immediately after selecting the Japanese section, or does it happen when you try to write or interact with a specific part? Also, have you noticed if this happens only with Japanese or with other languages too?

Meanwhile, here are some initial steps we can try on your Kindle device running Android 11:

1. Restart the device: Sometimes, a fresh restart can clear temporary glitches.
2. Clear LetterSchool app cache: Go to Settings > Apps > LetterSchool > Storage > Clear Cache. This won't delete your data but can fix minor app hiccups.
3. Update the app: Make sure you have the latest version of LetterSchool installed from the Amazon Appstore or Google Play Store if available.
4. Check for device software updates: Go to Settings > System > Software Update to ensure your Kindle’s Android version is up to date.
5. Try switching language settings: If possible, switch to a different language in LetterSchool, then switch back to Japanese to refresh language resources.
6. Check for permissions: Navigate to Settings > Apps > LetterSchool > Permissions, and ensure everything needed is allowed (such as storage, if applicable).

If these don’t help, it might be related to the app’s handling of Japanese characters or input methods on your device. This has been noted as an issue in other apps too, often related to keyboard compatibility or language input engines crashing an app.

Could you also confirm if you are using any special Japanese keyboard or input method on your Kindle? Sometimes third-party keyboards or incomplete language packs can cause crashes.

Let me know what you find with these steps or if you notice any specific error messages or patterns. That will help me assist you better!