What economics models students (should) have learned?

    I recently have had a look of the high-school economics curriculum in Hong Kong. I've found that students have been taught very small number of economics models, which are the essential elements in economics. 
    Economics models represent economists' understanding of how the real world works. A description of what happens in the real world or in a hypothetical world must be involved. This involves how typically an issue will happen in some ways, and, if the model is useful, we expect that similar things will happen in similar circumstances. Simply explaining a concept and saying that a concept can be applied in some circumstances is not a model. For example, explaining what is inflation, long term vs short term, opportunity cost, etc is NOT a model although these concepts may be used in a model. 
   By this standard, I find that the high-school economics teach students only three models: demand and supply of goods, demand and supply of money, and aggregate demand and supply. In short, it is only demand-supply model in several contexts. 
   There are also two models that students may learn but it is not necessary for them to learn. In the elective part of the curriculum, students may need to learn how a monopolist sets the price for profit-maximization. This is a model. Also, they may need to learn how countries can specialize and trade with each other to attain a mutual gain. This is also model. 

   In my view, of course, I think they have learned too little about models. When these students study at university, typically they will find it difficult to learn much more models. In fact, they will find that they need only to learn many more models, and no more. They will find that economics is not what they expect (as their impression about economics is mainly from high schools). 

   Perhaps that's what things should be. High-school students may not need to learn so many models. They are too ignorant of what the economy is about. So, their urgent task is to learn some concepts that can be used to do simple economic analysis and some facts about the economies. Well, I am not expert in high school teaching. I cannot comment on whether this is the justification for the current curriculum design. But as an university teacher, I am worrying about the wide gap between high school and university education may potentially generate severe impact on students' learning experience in economics. 

   I am not proposing the high-school curriculum should incorporate more models. But I am here to explain what extra models should be taught if one wants to get sufficient tools for doing essential economic analysis. 

   The point is, demand-supply model belongs to the class of equilibrium models in economics. Equilibrium models explain how forces in opposing sides (or with conflicts of interests) may arrive at a stable outcome when different sides interact under some rules of games. Be it for a single good, or for the whole economy, equilibrium tells you the whole picture, given your understanding of how individuals will take actions. 

   However, equilibrium models do not tell you how individual will take actions. If individual actions are not explained, we may need to take some patterns of actions for granted. For example, students are told that when price of a good increases, the quantity demanded for this good will decrease. This is a pattern of individual actions. But why individuals will follow this pattern? If we don't explain it, we don't know if there will be exception, and we don't know if this pattern may change. If the real world is changed, not like the world we encounter today, will the individual action pattern change? We don't know if we don't have a model of individual action. 

   Hence, you can see: the point is that you need more models. In particular, how individual consumers or producers make decision and take some actions? We need to understand the mechanisms behind their decision-making. Thus, at university, students will be taught the model of consumer behaviours and firms' behaviours. Of course, some more parties' behaviours under different circumstances will also be taught. But it is basic that students need to understand consumers' and producers' behaviours. 

   I hope my students understand why they need to go through the trouble in learning so much more.