There have been lots of questions recently about what to do on 'taster days'. Uncontained subject enthusiasm normally does the trick, but there is some competition with other subjects, so occasionally you might feel the need to play the game and, quite literally, play a game.
In previous years I have done the Public Goods game. I like this because it demonstrates how economists think by looking at what's rational and the incentives involved, something which is otherwise hard to communicate in single taster session. I normally start by explaining the central problem in Economics, Samuelson's three questions and how these questions can be answered either by government, or by producers and consumers coming to an agreement. I then go on to say that the latter normally do a pretty good job, but not always, and that we sometimes end up in a social dilemma.
I briefly explain the terms rivalrous and excludable, usually in the context of some sort of chocolate ("You want it? Tough, because I want it, and if I eat it you can't, and I can stop you from eating it by putting it in my pocket and fighting you off..."). We then talk about non-excludable and non-rival and go through the standard examples.
I then introduce the game. I normally prefer to do a demonstration with 5 or so students rather than the whole class playing independently because it gets quite complicated if you don't know the group well (I sometimes do that when I come to teach it properly, and I use the score cards here.) Because we're playing the 'student numbers' game, I sometimes jazz this up by sellotaping golden tickets to the bottom of selected seats for extra excitement. Those students come to the front and are given a mini whiteboard and a pen.
I then explain the game. They are given 10 coins/tokens/pounds/whatever. They can keep them all, contribute them all to the community investment chest or do a bit of both. Since the community chest benefits everyone, each person will end the round with whatever is in their pocket, plus half (each) of whatever is in the community chest. The fraction is arbitrary, but an easy one makes the calculations more manageable.
I then get them to face the front (backs to the class), write on their board the number of coins they want to contribute to the community investment chest and hold it up above their head so the rest of the class can see but the other participants can't. At this point, it really helps to have a Year 12 or 13 student on hand to log all the info. I've found it best to get them to fill in a table in a powerpoint so you can then project it easily at the end and compare rounds. When all the students have got their board up, add the total in the community investment chest and inform them of the amount they each receive from the community chest. Get them to clean their whiteboard off, and write their final total on their board. At this point, they can all turn around and look at what each got. Congratulate the 'winner' (this reinforces to the others that they need to rethink their strategy). Also make a note of the aggregate score of all of the students put together.
Then you do another round. You can either get 5 different students up, or stick with the same ones. Reset to 10 coins each. This time you are likely to see less investment into the community chest, and a lower aggregate score. You can ask why people chose the numbers they did, discuss what 'homoeconomicus' would do, have a bit of a conversation about rationality etc. If you had any investment into the community chest, you might want to rerun again: pretty soon you'll end up with no investment.
Explain how we see this in public goods. Everyone wants to benefit but no one wants to pay. Just like no one invested in our community chest, no one rationally buys the public goods. So what do we do? Go without them? Students normally come up with the idea that everyone should be forced to pay by law (tax) and that can lead you off on a different discussion. Students might also suggest that if everyone else knew what you were contributing, you might be less likely to free-ride, which is another nice discussion - how humans get utility from social approval. You might also want to discuss how we can maximise the benefit to society and see how this is sometimes different from how we would maximise the benefit of an individual.
This year, I might make a change and do these vaccine allocation activities instead. It's timely, but also the benefit here is that the focus really is on the Economic problem, so you don't need to skip ahead to future topics. The last task can be set as 'Summer work' which many schools require, and is quite structured but should still give you an idea of how well students get on with reading and how readily they can come up with advantages and disadvantages of different methods of vaccine allocation. The downside is that is doesn't convey the economic approach quite so well.
I know other teachers have used the Oligopoly game, the Efficiency vs Fairness activity, the Dialysis Machine activity or some form of the Desert Island Game as part of their taster days, so if you're looking for economics taster activities, you might want to take a look at those too. Another option would be to use these posters as a basis for a silent debate or other discussion task.