Cardinal Square is enrolling families in an after-school English class for grades 3 to 8, and it lists a math class beside it. The writing program is built around about 30 minutes a day on a schedule a family can adjust, daily reading, and one essay a week from a first idea to a finished draft. AI feedback asks questions, points to reading examples, and comments on revisions. The company states that the AI does not write or rewrite anything, so the student writes every sentence and makes every revision. A teacher reviews and signs the weekly progress report, which covers the work, the skills practiced, and what comes next, and parents can meet an academic advisor once a month. The first month is free. English is then $29 a month, and math is billed separately at the same price. Y Combinator lists the company in its Fall 2026 batch as a two-person team in San Francisco, founded in 2026. The plan on file is to start unaccredited with this after-school writing class, then build full accredited schools in which educators and AI teach together. Bryan Hong, CEO, previously led Shofo, a YC W26 company. Jai Pal, CTO, previously interned in core engineering at Snowflake and worked as a quantitative developer building machine learning and trading infrastructure.