In the menu under [settings] you can find the button to unlock teachers mode.
When you click on “unlock on Google Play” it will go to the Google Play store where you can buy “unlock the app” so you can activate teachers mode.

In teachers mode you can set all the tense times and yes/no/yes?/no? to your needs plus you’ll be able to save those configurations in the [student profiles] settings so that you can switch between students quickly.

You’ll also be able to reset the app to the beginning and set a custom level to start with.