As school districts face tighter budgets, growing pressure to strengthen family engagement, and the expansion of phone-free school policies, many are rethinking how schools communicate with families.

The 11-year-old ed tech unicorn led by Under 30 alumni Sam Chaudhary and Liam Don was quietly valued at $1.25 billion by Tencent last fall as part of its virtual push. ClassDojo president Liam Don is ...