Launch HN: Bloomy (YC S26) – AI-powered mastery learning for K-12

Bloomy, a YC S26 startup founded by former teacher Alex Southmayd, is an AI-powered mastery learning platform for K-12 students that combines personalized learning paths with an AI tutor to address learning gaps in math, English language arts, and writing. The platform diagnoses skill gaps, places students on individualized learning paths, and uses a Socratic AI tutor to guide students through lessons without simply providing answers, aiming to make one-on-one tutoring affordable and accessible to all students. Students progress through three stages (Base Camp for concept introduction, Climb for guided practice, and Summit for independent work) and must demonstrate at least 90% mastery before advancing to the next skill.