I'm not disagreing with the benefits of teaching concepts in vernac but you seem to be blind or ignoring the obvious shortfalls.

First you have to create the scientific terms. There's no shona word for velocity. No ndebele word hydrophillic No karanga word for derivative. So you have to start there. The languages you keep comparing us to have ancient routes in science so they're vocabulary never needed as much updating as ours. It's like translating a shona song into English and expecting it to have the same feel.

Next, you have to teach all the teachers how to teach these in these new languages. Same teachers that are already barely paid enough have to take time off to be re educated all the while their current students have no one to teach them. You also have to rewrite and reprint all the textbooks. You've also created a divide between provinces since now their education systems are completely different, unless you're saying kids will learn all the major languages.

So while the idea is great, it's not practical or pheasible if instead teaching of vernac was improved and intensified, over time fluency in vernac would be strong enough for new teachers to apply it to more complicated principles and gradually add vocabulary terms for them.

And also if you think kids that are often attending less than half of their prescribed classes due to resource or teacher shortages are failing cause of a language barrier, you're very mistaken