In my 26 years of teaching 8h grade earth science, I have always asked students for input regarding their work/lab partners during the first week of school. It's amazing how much information you can amass from their responses including: the besties, the trouble makers, the socially challenged, and the kids who need a little TLC. Sure, it takes more time to go through all the papers, but ultimately I love using this form. The best feeling is when you create a group from students who have no one to request, and they end up becoming the best of friends. This is a great tool, even if only to learn more about your students at the beginning of the school year.