Does anyone know who wrote a book called "julie"?

I used to read some books while I was growing up called "julie", cathy", "virginia" and so forth. All these books were about teeagers growing up and the hardships they went through. I do not know how many books there are total but I do know there are quit a few of them. If anyone knows the name of the author or the name of the series I would be so greatfull =)