Collaboration allows the two teachers to combine strengths, share responsibilities, and learn from each other, bringing the best of both their experiences together to create an improved student learning environment. When co-planning, both content and technology standards can easily be combined thanks to each partner's specific focus. Other advantages of co-planning include the sparks of innovation that begin to fly when more than one teacher contributes their perspective to a unit or lesson, and the opportunity this allows to customize the pedagogical and technology experiences for that particular class or grade level.
via techlearning.com