Section 2A. Every person in control of a deaf child between seven and eighteen shall cause such child to attend some suitable school, approved by the department, where the deaf are taught speech and speech reading; provided, that this section shall not apply to such a child whose mental condition or whose physical condition in other respects than deafness is such as to render such attendance inexpedient or impractical or who is being given private instruction, approved by the department, during the time the public schools are in session. Failure for one month during any school year by any person in control of such a child to cause his attendance as aforesaid shall, on complaint by a supervisor of attendance, be punished by a fine of not more than twenty dollars.