Gary Miron and Charisse Gulosino have prepared a guide and analysis of the growing online cyber schooling sector which produces inferior education. Nearly 300,000 students are enrolled in these schools, their performance is unimpressive, decisively worse than public schools, and their graduation rates are abysmal. Yet, they are profitable - which means their owners will continue to seek a greater market share. The authors recommend that policymakers should slow or stop he growth of these schools and closely monitor and sanction those that fail. They should be required to devote more resources to instruction and limit class sizes. Diane Ravitch says : "these schools should not be allowed to operate for profit. They should not be allowed to advertise for customers. they should be closed if they are bad schools. That would be a start.