Darsel is a personalized math learning chatbot which allows students to practice and learn curriculum-aligned math through simple messaging channels such as WhatsApp, Facebook Messenger and SMS. Darsel is designed to be easily accessible by K12 students in low- and middle-income countries where data- and device-related constraints often prevent adoption of conventional education technology solutions. Darsel partners with public school systems and math teachers to reach students, and its adaptive learning algorithms are designed to identify and address learning gaps.