N.H. Rev. Stat. § 186:5
The state board shall have the same powers of management, supervision, and direction over all public schools in this state as the directors of a business corporation have over its business, except as otherwise limited by law. It may make all rules and regulations necessary for the management of its own business and for the conduct of its officers, employees, and agents, and to secure the efficient administration of the public schools and the administration of the work of Americanization, in teaching English to non-English-speaking adults and in furnishing instruction in the privileges, duties, and responsibilities of citizenship, which is hereby declared to be an essential part of public school education. It shall be the duty of school boards and employees of school districts to comply with the rules and regulations of the state board.
RSA 186:5
1919, 106:5. 1921, 85, I:5. PL 116 :5. RL 134:5.