Cooperative learning is unequivocally the best strategy to use in second language classrooms. By using positive interdependence and personal accountability, it enables the learners to get the most practise and knowledge out of every activity and lesson. I have been able to observe this strategy being used in my practicum and it is clear that this strategy is making wonder in the ESL classroom. However, students love to be surprised and to try new things, the best way to do so in a cooperative learning classroom is to integrate a little competiton. This is exactly what Challonge intend to do as a tournament maker. However, in the classroom context, it is important to create a healthy competition, i.e. it is meant to be fun, it is relatively short, it has a high degree of energy and everyone has a reasonable chance to win. More information about integrating competition in classroom can be found in Transformative Classroom Management. By John Shindler.
Challonge is an automated tournament brackets maker. It is really simple to use, you simply name the tournament, choose the type of tournament and enter the name of the participants. Then, you only click on an event to specify the winner and the loser and the tournament continues. There are four types of tournament: single elimination, double elimination where a second tournament take place with the losers, round robin where everybody plays versus everybody once and swiss where points are given according to the outcome. You can whether make your own participants arrangements or let Challonge randomize the events. To fully enjoy the parameters of Challonge and to be able to save the progress of your tournament, it is necessary to subscribe to the website. The tournament can also be viewed by its participants via a shared URL. There is many more specified options in wich one can allow other administrators to enter the scores or set the notifications system. Here is a youtube video to learn how to use Challonge in the class.