Hi
First of all, 3 kids CAN work, if needed, but the leader needs to monitor the group carefully to make sure everyone is included.

As for the rest of it, kids get paired and assigned to groups in school all of the time, and they manage.

We do several things:

1. Let the kids pair up as they please, but tell them ahead of time that if they choose not to work together and cooperate, the adult will then move them. (this is rarely an issue for us)
2. Count off or do a random pairing
3. Assign pairs/groups by birth month.

It is important that part of what we teach is respect for others as well as compassion. Adults need to be on the look-out for the child who does not get "picked". That is another reason to do random pairings. You can then switch part way through the lesson time as well,if that seems appropriate.

As for complaining, why would we allow that? Adults set up the rules, give children the option to choose when that is appropriate, but after that, our role is not to make sure that the children have their own way in everything.

When we set up our expectations, and the children know what to expect, and that they can expect to be treated with fairness and respect, my experience is that the children will follow through with fairness and respect themselves.

Not always of course, but that is because they are children and are still learning! (and doesn't that apply to all of us adults as well?)

I guess the bottom line is that after a time, we know our kids pretty well, and we can respond to what they need in ways that are helpful and appropriate.

Have fun with the computers; I know the children will, and a lot of your worries will resolve themselves because the children will be excited and engaged.
blessings
Jan S