Bidding Wars

I have a lot of free time today so here is another activity. The title is bidding wars, but it's similar to some of the other auction activities on this site. I have used this for my third years and they really enjoyed it, so I thought I'd share here. One thing to note is that the way I run it is very hands on, so you need to be very focused when doing this game.

Preparation:
- A list of sentences practicing the target grammar. The sentences are either correct or incorrect.
- Fake money
- Timer
- (optional: lottery box)

Instructions:
I ran this activity as a group activity, so students got into groups of 5-6.
The students are all given 1000$ in 100 bills to start. The groups are given a list of 20+ sentences practicing the target grammar, with the catch being that some sentences are incorrect. They are given 5 minutes to look over and analyze which sentences are correct, and think about how to correct the incorrect sentences. After the 5 minute timer, its time for the game to start.
The JTE or ALT will call out a random sentence from the list, and start a 1 minute 30 second timer. In that time, students must find the sentence, decide if its correct or incorrect, and bid money to own the sentence. The auction ends when the timer runs out. Possible scenarios upon winning the auction:
If they say that the sentence is correct, and it is correct, they obtain the sentence and get all the money they spent back.
If they say the sentence is incorrect, and it is incorrect, they must then correct the sentence. If they correct the sentence, they obtain the sentence and get all the money they spend back.
If they say the sentence is correct, and it is incorrect, they lose their money and we move on.
If they say the sentence is incorrect, and it is incorrect, they must then correct the sentence. If the sentence is still wrong, they lose all their money.
This part is a little confusing, so its best if it's demonstrated with the JTE.
The winners of the game is the group with the most sentences.

Some issues I've run into and how I worked around them:
- Several groups have hit the highest bid number right from the start. They thought it was funny when several groups called out 1000 at the same time. I had them rock-scissors-paper for who answers. For the first 3 rounds I allowed this method then changed the rules a bit to keep it fresh. I would allow them to only increase the bid by 100 for each group while decreasing the time on the timer.
- Some groups don't have the chance to participate. I fixed this by introducing the paid rule halfway through. Now students would have to give their money regardless of if they got it correct or not. This makes them think more about their money while giving other groups the chance to play. One way to make it more fun is through the optional lottery box. After spending money, they had the chance to try and get half back by pulling from a box. If they got a O they got the money. If they got an X they didn't. The classes had good reactions either way.
- Some groups dont have money from above. I start giving back 100 to everyone after each round.

Overall, this game is very flexible for grammar content, however it requires you to think a lot on the spot to facilitate the game better for the classroom. Let me know what you think.