Complex sentence: In Guatemalan Mayan communities children are often expected to take part in these practices, and when schools became prevalent, children who were not seen as providing valuable contributions to family and community endeavors may only then be sent away to school to make use of their time.
Split into simpler sentences: In Guatemalan Mayan communities, children are often expected to take part in these practices. When schools became prevalent, children who were not seen as providing valuable contributions to family and community endeavors may only then be sent away to school to make use of their time.