Charter schools are one of the only topics that earn praise from both Democrats and Republicans, but John Oliver found many of them are operated even more poorly than a restaurant that serves “sh*tty piza.”

They were first established about 25 years ago as educational laboratories and have since exploded in number to more than 6,700 charter schools, which educate nearly 3 million students and are backed by celebrities such as Sean “Puff Daddy” Combs, Andre Agassi and the rapper Pitbull.

“Look, when Pitbull has a charter school, it seems like it might be worth taking a look at them,” Oliver said.

Proponents point to news reports about successful charter schools, but critics argue those schools overstate their successes, divert public resources and siphon off talented students.

One study found that charter school students had a slight edge in reading and were about the same as traditional public school students in math, but acknowledged that performance was uneven across the states.

“And that is putting it mildly,” Oliver said. “Because around the country, there have been charter schools so flawed they don’t make it through the school year.”

A Florida newspaper found that 119 charter schools had closed in the state between 2008 and 2014, including 14 schools that never even completed their first year.

One of those schools lacked even a building and instead shuttled students to classes at churches, reception halls and a city park before suddenly closing after just seven weeks.

Its director, Trayvon Mitchell, apparently plagiarized parts of the school’s 400-page application from another charter school application filed a couple of years earlier, Oliver found.

“That behavior might not be illegal, but it’s certainly unethical,” Oliver said, before pointing out that Mitchell’s charter school handbook defined and prohibited plagiarism. “So the application for Mitchell’s school would also have been grounds for him getting thrown out of that school.”

Mitchell is now awaiting trial on grand theft after prosecutors accused him of spending school money on himself instead of students.

Charter schools are paid about $7,000 per student — and can add up to nearly $5 million for some schools, such as Philadelphia’s Harembee Institute — which was busted in 2010 for operating an unlicensed bar in its cafeteria after hours.

“A nightclub in an elementary school is a recipe for disaster,” Oliver said. “Those are the two most vomit-prone populations in the world. They must have had to Febreze the shit out of that place.”

That school’s former leader pleaded guilty to embezzling nearly $80,000 from the charter school — which Oliver said isn’t an isolated incident.

“In Philadelphia alone, at least 10 executives or top administrators have pled guilty in the last decade to charges like fraud, misusing funds and obstruction of justice,” Oliver said.

Pennsylvania’s attorney general said earlier this month that the state had the worst charter school law in the U.S., which Oliver said was a dubious accomplishment over even Ohio — the “wild west” of charter schools.

Ohio has about 360 charter schools, and its governor, John Kasich, strongly believes in choice and competition in education — which he compared to pizza shops.

“That doesn’t work on any level,” Oliver said. “First, no one has ever called it a pizza shop. Plus, it’s a little hard to hear the man who just defunded Planned Parenthood talk about the importance of choice, and third, there is such a thing as paying for extra pepperoni like a normal person. Finally, the notion that the more pizza shops there are, the better pizza becomes is effectively undercut by the two words, Papa John’s.”

A review last year found that Ohio charter schools misused public money nearly four times more often than any other taxpayer-funded agencies.

Lisa Hamm, who ran Cincinnati’s largest charter school, accepted a plea deal in 2014 to misusing school funds to pay for jewelry, spa visits, European travel, veterinary care and a trip to see an “Oprah” television show taping.

A year before her plea agreement, Hamm used the Bible to justify her expenditures, saying that she was trying to develop a vision she wanted to share with students about what was possible in life.

“That is amazing,” Oliver said. “She’s just spouting a bunch of vague bullsh*t about inspiration, crossing her fingers and hoping people will buy it. And you know what? When you put it like that, I feel like she has a learned a lot from Oprah.”

Oliver also pointed out the Bible verse Hamm cited, Proverbs 29:18, contained “a f*cking important caveat”: “Where there is no vision, the people perish; but he that keepeth the law, happy is he.”

Ohio requires charter schools to be operated as non-profit organizations, but they may hire educational management companies — or EMOs — that can skim profits off the top.

“Yes, ‘education is first, last and always a business,'” Oliver said, quoting an EMO operator from a news report. “Take the L off ‘learning’ and what do you got? Earning.”

That EMO, White Hat Management, worked under contracts requiring each charter school to pay 95 percent — or more — of its state and federal money to the private contractor, which operated 32 of the lowest-performing schools in the state.

“If you do essentially the same terrible thing more than 30 times in a row, you’re not a management company — you’re basically Bill Joel’s ‘Greatest Hits, Vol. 2 and 3,'” Oliver said.

Ohio allowed charter schools to be overseen by nonprofit companies operated by the schools’ operators, who — at least in one case — spent more than $1 million on consulting firms owned by the same operators.

Online charter schools, which serve over 180,000 students, are even more outrageous, Oliver said.

“Some have an attendance system you would not f*cking believe,” Oliver said.

Cyber-charters sometimes don’t count students as absent until they’ve failed to log in five days in a row, but they’re still required to report attendance — so they often just say 100 percent of students showed up.

“That is just crazy,” Oliver said. “You’re basically giving kids a box containing video games, pornography and long division and claiming 100 percent of them chose the right one.”

Oliver said schools cannot be run the same as any other business, like a restaurant.

“The problem with letting the free market decide when it comes to kids, is that kids change faster than the market,” he said. “By the time it’s obvious that schools are failing, futures may have been ruined. So if we are going to treat charter schools like pizza shops, we should monitor them at least as well as we do pizzerias. It’s like the old saying: ‘Give a kid a sh*tty pizza, you f*ck up their day. Treat a kid like a sh*tty pizza, you could f*ck up their entire life.'”

Watch the entire segment posted online by Last Week Tonight: