Role of teamwork in schools????

This is not an academic refection. I just try to figure out the rationale behind team formation in our class.
I don't really get this team based work. As far as I observed, you have the really good teams that managed somehow or simply had the luck to get the best members, and then you have the teams that are made out of half good, half floaters. I define floaters as those persons that change teams due to their lack of contribution/low performance/lack of interest, etc.
The good teams are already locked and they don't let anybody in or out. They are happy of having the best students and they don't want to risk it by taking newcomers, and I do not blame them. I would do the same probably. These teams can easily manage the assignments even if only one person works on the task. My team takes the same approach. We take turns and each of us do a task during the period of a course. It is easier and saves time. It takes more to travel with the bus from Raslatt, find a empty room (which is very hard to find by the way), then start talking and arguing which solution is better and why. Usually these conversations take hours and nothing productive comes out. And even so, the one that is the most insistent gets his/her idea through. Better have one dictator per assignment.

But what about the other teams? The teams that have floaters in them? What about these free riders? These teams will always get such students and I tell you why: as we take new classes and have the opportunity to remake the teams, the poorly performing students are usually thrown out. The rest of the team is sick of covering for that person, for waiting for their mails and so on. But who will replace this student? Well... most probably another "lemon", because these are the students that cannot stick to a team, or better said the team does not let them stick. Good students do not move, and a wise team will do its best to keep it. If another team wants that student, they cannot get him/her because he/she comes in packages of 3-4 (depending of the size of that team).
Maybe I shout explain this in more detail.
First of all, you can really see differences between the students here. Some did other things rather than a BA in Business and have a hard time comprehending the material. Others have a hard time speaking English. And others just don't care and are here to have fun. I don't blame neither. All are great people! In my opinion, these students make around 25% of class.
Now, the usual team here is made out of 4 people. There is a high change that you will get 1 such student per team. The other 3 well performing students will stick together (part of the same team) for the next class. They cannot get 1 more good student, cause these "luxuries" come in package of 3. So they will get stuck with another lemon floater....
So what to do?
Well... nothing I guess.... You need to help these students catch up. Many want to learn, but you have to teach them everything, which takes a lot of time and stress...

But then I ask myself: is this fair? 50% of the grade is based on teamwork. Why should those teams that have all members above average get good grades even if their individual work was less? Why do good students in bad teams need to suffer?

In the long run, this problem will solve by itself. Good students will also move one by one (and be assimilated int he 3 person group) and poor performing students will eventually improve. But What to do till then?

The schools knows about this issue. Anybody can figure this one out just by comparing the quality of the team based articles submitted VS the independent finals.

The results of this will only decrease the reliability of the student's grades. It will make some poor performing students get overqualified jobs while others, who worked more than the average in order to make up for the teams' members, underestimated grades.

Who has to win? Well... the smart or lucky teams that managed to get all members above average from the start.

This writing was not meant to insult/praise anybody. I just wanted to point out the flaw in the system, which I just realized that it is pretty useless, cause the students know about it and the university also knows about it, as I previously mentioned. So, I guess that my work was futile, but I will post this anyways....

Good night and have a great weekend