Many of us are schooling children in multiple grade levels and sometimes we wonder, "How can I teach all these children what they need to learn?" The answer can be a simple one.
First, step back and think about what you want your school to look like. Do you want each student in his or her own desk? Are you trying to teach each one something different or are there similar topics? Have you considered teaching a concept to all the children at the same time even if it's over the heads of the younger ones?
I believe that in casual learning, students retain more information than formal training when there is pressure to remember events, dates and formulas. That has been my experience in learning myself and in the ways my children learn, too.
Condense teaching when possible. Call all the children together to discuss the respiratory system or when explaining the effects of World War II on people and communities or when laying in the grass at the park looking at clouds. Focus on the teachable moments and watch your children flood you with their creativity and knowledge!