How can Instructional Design be visual as well as engaging?

How can Instructional Design be visual as well as engaging?:  My dad used to explain astronomy to me using salt pots and oranges. The orange generally represented the sun, whilst the salt pots, ketchup bottles and whatever else was on the kitchen table stood in for planets and comets. He would then make them all ‘orbit’ each other, enlisting my help when he ran out [...]