The "Wisdom of Crowds" hypothesis has been introduced into many fields, but not into education. Groups with diverse knowledge and skills make better decisions than homogenous groups or expert groups. Diversity adds different points of view, which improve the problem solving ability of the group. The increased use of social networks makes it possible to employ the wisdom of crowds for creating new educational approaches for teaching-learning purposes. This article demonstrates the use of the wisdom of crowds for preparing lesson plans and learning units. All lesson plans and learning units improved following the wisdom of crowds. Collaboration of crowds can be used in many ways, including writing exams, classroom interactions, turning topics into relevant material for pupils, suggesting alternative methods of evaluation, etc.