We have seen incredible progress on education in the past 20 years. Ethiopia alone increased the number of children in school by 15 million in just 10 years. Globally, millions more children, especially girls, now get to go to school.

However, a dangerous experiment to privatize education in the name of efficiency is putting this progress at risk and making inequality worse. In developing countries, a child from a rich family is seven times more likely to complete secondary school than a child from a poor family.

The power of public education isn’t just about ensuring every child no matter their gender, ability, or family’s wealth, gets to go to school. It’s also about the power of education in the fight against inequality. A good-quality education can have an equalizing effect – giving kids opportunities they wouldn’t have otherwise had, which has the power to transform whole families and societies.

But when public aid money is given to private education companies who operate on a business model of making profit, evidence shows that who gets to learn, and what they learn, is compromised. Charging fees to families who can’t afford to pay them and cutting corners like paying teachers poverty wages only increases inequality, which hurts us all.

By signing this letter, you’re demanding rich countries and institutions like the World Bank invest their aid money in public education and stop funding profit-driven private education that excludes the poorest.

You can read the full letter, here.