it's time to go to school同义句转换为It's time for school。表示该上学了。It's time for school的例句：It's time for us to go to school（是我们去上学的时间了）。

It's time for school的例句：It's time for you to take them around your school（该是你带他们参观你的学校的时候了）；It's nearly time for school（差不多到上学时间了）。