As Montgomery County fills its high schools with advanced-level college-prep classes, many parents worry the district has pushed too far too fast, leaving what used to be the “typical” child left behind and stressed out.

Since 2001, the district has nearly doubled its Advanced Placement courses from 19 to 37 and greatly expandedits International Baccalaureate offerings. The rigorous classes, from multivariable calculus to studio art, are designed for students to earn college credits.