To refer to permanent or almost permanent qualities you use:
To refer to temporary qualities you use:
Él __ mi hijo y ____ feliz de estar aqui
Walk around somewhere and describe what people, objects and animals are using ser and estar. After doing that, sit down and write those sentences.
Example:
Go to the living room and if you see the window open, say "The window is open" in spanish "La ventana está abierta". It's monday, i am happy, my shirt is red, i am studying, i am from x country, 5+5 equals 10, etc.
The purpose is to use ser and estar in real life situations.