They would use group assignments sparingly and instead provide a lesson or activity that would incorporate most, if not all, of the class at one time. I find these are generally more beneficial to me, as it removes any awkwardness that a group assignment might have and opens the door to wider discussion so you can hear ideas you might not otherwise have heard differently. I generally find that using small group assignments too often is detrimental for me as it usually takes too long, leading to rushing the rest of the lesson.