We did this activity a few months ago and the youth are still talking about it. I have to give props to my uncle Bruce who did something similar when he was in the YM presidency several years ago. It took a lot of planning to get the logistics coordinated, but I think the end result was SO worth it!
As the kids showed up to the church I had them pick out bracelets from a box, the color they got determined which team they were on. They were then grouped in their teams and the leader going with them was given the rules. The rules stated they had to be back by a certain time, they had to go to each location in the order on their list, and they had to take a picture with the entire team at each location. Some examples of things they had to do go as follows: Go to the grocery store and everyone had to return two carts, go to a restaurant and everyone had to hold the door open for someone, etc. We set this up as a race, so the kids were competing to be the first team that went to every location to be back first.
Here is where the twist comes in! :) At every other location the youth went too I planted someone there to have a problem, to see if the youth would stop the race and risk coming in last to help them. At one location someone dropped their groceries, someone locked their keys in the car at another and finally someone lost a contact lens. One important note: Although this was a joint activity, I did not let the other leaders in on the twist. I didn't want them to sway the youth, and I thought it would be a great learning experience for everyone.
By the time the youth went to each location and came back to the church, I had all the "helpers" back at the church waiting. You should have seen the looks on their faces, leaders included! I then spoke quickly about how sometimes life feels like a race, and we are always striving for the ultimate goal. In life that is reaching the celestial kingdom with our families, in this game it was coming in first. However no matter how anxiously we are engaged in this righteous cause, we can never forget about our brothers and sisters that need our help. I think it had a powerful effect on everyone in attendance, and I hope the youth will remember it for years to come.