The United States education secretary has warned that skyrocketing enrolments have pushed many schools to hire unqualified teachers, writes Jon Marcus. “Too many school districts are sacrificing quality for quantity to meet the immediate demand of putting a warm body in front of a classroom,” Richard W Riley said.

A huge increase in the number of students has combined with the projected retirements of many teachers to create a growing teacher shortage.

Officials expect that they will need to recruit at least 2.2 million new teachers over the next decade. Some states have waived the normal certification process.