From a report titled Invisible Schools, Invisible Success

Virtual schools are popular because they are profitable. Estimates show that “revenues from the K-12 online learning industry will grow by 43 percent between 2010 and 2015, with revenues reaching $24.4 billion.”

More than 200,000 K-12 students are enrolled in full-time virtual schools across the country; when expanded to all students enrolled in at least one course, the number explodes to 2,000,000. The more children enrolled in virtual schools, the greater the profit for the companies.
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In December 2004, the American Legislative Exchange Council (ALEC) approved the “Virtual Public Schools Act.” That model bill sparked a rush by private companies to embrace virtual schools and virtual learning across the country. Today, there are more than 230 nationwide accredited private virtual schools in the country.
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ALEC is closely tied to the virtual school movement, having pushed its “Virtual PublicSchools Act” on behalf of corporate members of its board since 2005. The law was adopted by ALEC through the work of its Education Task Force,comprised of corporate lobbyists and conservative legislators. According to the Center for Media and Democracy’s website, ALEC Exposed, two of the three co-chairs on ALEC’s Education Task Force work directly for virtual school companies

Mickey Revenaugh, Co-founder and Senior VicePresident of State Relations for Connections Academy,a virtual school company; and
Lisa Gillis, Director of Government Affairs and SchoolDevelopment for Insight Schools, part of K12 Inc.

K12 is one of the largest virtual school operators in Ohio. The Ohio Virtual Academy, represent about 26% of K12′s annual revenues. We've previously demonstrated that virtual schools in Ohio are manufacturing profits at the expense of education, primarily by packing their virtual classrooms. These packed virtual classrooms have a significant effect on students

–OVA enrolled a total of 18,743 students cumulatively throughout the 2010/2011 school year with 9,593 withdrawing by the end of the year, for an astoundingly high churn rate of 51.1%

"[…]these cyber schools might as well have a turnstile as their logo for the volume of withdrawals they experience.", noted one researcher.

To highlight the emphasis K12 puts on profits above education, comes this leaked email from their CFO in Pennsylvania

An April 23, 2010 e-mail from Kevin Corcoran to a host of his colleagues is likely the sort that, in one form or another, millions of Americans deal with regularly during the work day.

Bluntly noting “We have not made the progress we need to in this area,” Corcoran adds, “More than $1[million] in funding” is in the balance.”

“Anyone who has not fulfilled their obligation in this area should not be surprised….when it’s time to discuss performance evaluations, bonuses and raises.”
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In the e-mail, Corcoran, who is Agora’s financial chief, was miffed because 81 “IEPs,” short for individualized education programs–basically customized teaching plans for Agora’s growing populace of special education students–hadn’t received the necessary signatures; without them, various school districts would not release reimbursement of $15,000 per pupil (or higher) to Agora, and thus K12, to educate a student populace that have had profound troubles meeting educational expectations.

More concerned about bonuses and raises, than the fact that students have outstanding IEP's that are not being addressed. This is part of the educational mess ALEC has and continues to try to create.