Schools in Wisconsin come in four basic flavors. Please don't confuse or conflate them.
- Public schools. The public schools are required to have fully licensed ("highly qualified" is the No Child Left Behind terminology) teachers, assistants, and administrators. The public schools must administer standardized tests in grades three through eight, plus ten, and publish the results along with other NCLB-demanded data, such as attendance, graduation, and retention rates, and oodles of demographic data. The schools are fully funded through taxpayers' money (except for all the bake sales and fundraisers they have to hold to fill in the gaps). They are required by law to provide services to special education students, and students who are English language learners, regardless of cost. They are operated by about 420 districts throughout the state as mandated by Article X of the state Constitution, under various parts of state statutes 115-121.
- Charter Schools. Charter schools are also public (and non-religious) schools. Really. Like public schools, they must have fully licensed professional staff, and they must administer the same tests and publish the same data as the traditional public schools. They are also fully funded by taxpayer dollars and authorized under state statute 118. The difference between charters and the traditional schools is who runs them: Charters are operated by independent, authorized groups who contract--or charter--with the local school district, currently only Milwaukee or Racine. (The Milwaukee Public Schools sometimes charters with itself to run its schools as charters; these are called instrumentality charter schools, as opposed to the non-instrumentality charters run by other groups.) The independence from districts theoretically allow charters to innovate and move more quickly in response to demands from parents. Read more on charters at the DPI.
- Private Schools. These are schools, also covered by section 118, that get no (or almost no) taxpayer money at all. They can be established by pretty much anyone, can be staffed by pretty much anyone, can teach pretty much anything, and have only to meet minimum requirements to be allowed to function. They can admit whom they want, and are not required to admit or provide services to special-needs students. They don't have to give any tests at all or publish the results, or any other data about the school. Many private schools, though, choose to employ licensed teachers, teach special-education students, and to give standardized tests. See the DPI's page on private schools for more.
- Milwaukee Parental Choice Program (Voucher) Schools. These are private schools, mostly religious in nature. These schools set a tuition rate, and can pick and choose who attends among the paying customers. They can also, if they appy to the DPI, accept students who meet certain economic criteria and receive a voucher to cover their tuition, currently $6,501 (or less if tuition is lower than that). The voucher program is limited only to schools in the city of Milwaukee, and schools that accept voucher students face a few more hurdles than the private schools described above. They still don't need licensed staff, and still are not required to give any particluar tests (though they must adminsiter something) or publish any data about themselves beyond the attendance data submitted to DPI as a prerequisite for getting their voucher payments. They are required to admit voucher students based on a lottery, rather than any selection criteria, but are not required to provide any special education (or other) services to students they admit who might need them. And they must prove to DPI by later this month that they either have accreditation, or are working on it. The DPI has a section on voucher schools, too. (Updated 12/12 for accuracy on the testing part.)