<sod>More recently, multi-state agreements ensure that basic requirements are universally met by all state school systems.  Thus, all children are required to attend one type of school (five or six days a week) from the age of 6 to the age of 16.  A pupil may change schools in the case of exceptionally good (or exceptionally poor) ability.  Graduation certificates from one state are recognized by all the other states.  Qualified teachers are able to apply for posts in any of the states.<eod>
<sod>Multi-state agreements ensure that basic requirements are universally met by all state school systems.  Thus, all children are required to attend one type of school (five or six days a week) from the age of 6 to the age of 16.  A pupil may change schools in the case of exceptionally good (or exceptionally poor) ability.  Graduation certificates from one state are recognized by all the other states.  Qualified teachers are able to apply for posts in any of the states.<eod>