With the JetBrains Academy plugin, available both in Android Studio and IntelliJ IDEA, you can learn Kotlin through code practicing tasks.
Take a look at the Learner Start Guide, which will get you started with the Kotlin Koans course inside IntelliJ IDEA. Solve interactive coding challenges and get instant feedback right inside the IDE.
If you want to use the JetBrains Academy plugin for teaching, read Teaching Kotlin with JetBrains Academy plugin.