“Brush your teeth”, “Exercise”, “Tidy your room” don't have to be added every day. When creating a task, choose “Repeat”: “Every day”, “On weekdays” or “Choose days”. On each such day the child gets the task again, with the same points. Yesterday's unfinished one goes away by itself; one marked “I did it” stays until you accept it.
Repeating tasks are listed under “Repeating” in “Tasks”. To stop one, tap “Stop repeating”: today's unfinished one goes too. The new day follows your phone's time.