True, and even much wider than the educational system, but I would probably rephrase to say that this makes human intelligence predictable within narrow domains. A math class strives to make students predictable when attempting to solve math problems, a legal system hopes to make humans predictable in the domain of violent conflict resolution, a religion hopes to make humans predictable in metaphysical inquiry, etc.

But human intelligence itself is fully general (in that we defined 'fully general' to mean 'like me'), so there's not really any form of training or education that can make, or attempts to make, human intelligence predictable across all domains.