Parents, what's the best AI tutor for kids?

What's the best AI tutor for kids and quite frankly, are any of them really any better than just using chatGPT or Claude or some other tool not specifically focused on kids? Would love to hear what you've tried, liked or hated. Asking because I run a homeschooling marketplace and looking for tools for our tutors and parents to use with kids. Excited to hear your thoughts!