Thousands of Greek high school teachers take to the streets in Athens.<br/> <br />They have been threatened with arrest if they proceed with a planned strike later in the week.<br/> <br />The strike would affect university entrance exams.<br/> <br />(SOUNDBITE) (Greek) HIGH SCHOOL TEACHER KAITY THOMAI, SAYING:<br/> <br />"It is illegal and unconstitutional. Based on the constitution, since 1975 it is every workers personal right to strike, throughout the entire modern world."<br/> <br />The government plans to invoke emergency legislation that forces strikers to return to work or face arrest.<br/> <br />But protesters were clear in their message, " Disobey and strike" they chanted outside parliament.<br/> <br />The teachers are also protesting against plans to extend their working hours by an extra two hours a week and the transfer of 4000 teachers around Greece to fill staffing holes.<br/> <br />The transfers they say will split families.<br/> <br />The emergency legislation has been used twice by the 11-month old government.