Few kids in one of the programs were asked to Act out the concept of day and night. And they all were fumbling - not sure who moves around what and how the WHOLE day and night works.
This project did nor start with any  mind map. But with questions

How is day and night are formed?
Why does sun rises in east? What duration does the earth rotate?
How does moon changes shape?
What is Eclipse? How and whne Eclispe happen?  - Solar and Lunar?
How are seasons formed?
How does summer have long days and winter have short days?
Do star shine?
How earth rotates around the sun?
How day and night are formed?
How the moon shapes changes?
How earth rotation effects climate?
What are the different types of climates in the world?
What is the difference between Season and weather?