Here �s another idea...
You can play "Grammar Auction"....
Write many,many, many sentences on strips of cardboard (not too small). Write some sentences correctly and some with mistakes. Obviously, you will have all kinds of tenses in these sentences (the ones you need to practice)
Then, you will divide the group into teams of 4 or 5 ss. (tell them beforehand they must bring candy, or paper money, whatever you choose)
once you have them seated in their teams, you will show a sentence, and have them "bid" and buy it for their team. Highest bid wins it.
Each team must buy at least 3 - 5 sentences (you choose according to your time) when all the sentences have been sold, give ss a few minutes to work with their partners and decide whether each sentence they bought is correct or incorrect.
You then ask a member of each team to pass to the front, show one of their sentence, and say if it is correct or not. If they say their sentence is correct, and it IS correct, then you give them back their "money" they paid for. If they say their sentence is incorrect, they must write the correct sentence on the board. If they do this correctly, then you pay them double.
if they make a mistake, for example, say it �s correct when it �s incorrect, they must pay YOU double of what they paid.
Do this until all sentences have been presented.
So, keep in mind you have to have lots of candy (the little wrapped individual ones are not expensive) so you can PAY ss for correct answers.
After they the game is over, they can eat their sweets!!!