I’m sorry, but it doesn’t sound like you read the article.

Some salient quotes:

Companies cited a variety of ways they gain access to student digital activity, including browser plug-ins, API integrations and device software.

Many companies collect and flag sensitive data, including students’ private messages and search histories.

So, they work with shady spyware companies to collect private student data, retain it, and then try to sell it to schools.

I, for one, am fucking shocked!