My school was 1-8. My b’day is in September, but a lot of my friends had already turned 14 when we graduated in June.
As soon as you said 1-8 that says it all. Most (though obviously not all) elementary schools do not go that high. There are what are known as junior high school or middle school.
I am guessing you went to a private school. Personally I think it is nuts to have 13-14 year olds in the same area as those who are 6-7