Is there really a difference? I feel like if you don’t know something, that kind of makes you stupid, right? If you don’t know historical facts or mathematics—at least the harder stuff, like algebra or calculus—or if you don’t know about advanced political topics, then you’re kind of a stupid person, not just ‘ignorant.’
By feeling, stupid feels like lack of ability to learn and ignorant feels like lazy/avoidant of something you could learn (though you could also be kept in ignorance by another person/a system)