When you say teaching aids that would involve a variety like visual aids, audio aids, play-acting and even actual examples. One of the most effective teaching aids is the immersion where the students not only see and hear but also feel what the lesson is all about. One example is the laboratory class where the teacher would show an experiment. We were really amused no end when we saw a boiled egg with no shell that entered a bottle with a small mouth. It was more amusing when the teacher made the egg go out of the bottle. The egg remained intact.