Ask the first student a question (usually very easy) and if they get it right then move on to the second student in the group and ask if they would like to continue or 'bank' the $500, the questions I use slowly get harder but in general they are relatively easy (it's more fun that way, plus they're 50/50 so they always have a chance). During these questions they aren't allowed any help from other students (unless they're using a lifeline, which I'll get to soon).
A few examples of the easy questions I use (for Japanese students learning English):
Doraemon has no ears - True
There were 5 members of the Beatles - False
Anpanman's weakness is water - True
I have 4 arms - False
We live on the moon - False
The sun is hot - True
I have around 50 ready to ask them but I don't find it hard to think of new one's on the fly if I run out during the lesson.
To add to the fun, give them 2 lifelines that they can choose to use at any stage during their team’s turn (they can only use each lifeline once per round).
Phone a friend - Call someone else in the team and ask them for help (feel free to make them pretend that they're actually talking on a phone for laughs).
Ask the group - Let the team discuss what they think is the best answer.
That basically wraps it up, with 4 groups it takes around 15mins to get through 1 round. Keep track of how much money each team puts in the bank and you can add it up to see which team wins.
I've had a lot of fun with this game as the students really get into it, they put pressure on each other to try just one more question and it’s always funny when they play it safe and 'bank' money rather than taking a risk. Have fun and enjoy this ESL classroom activity!