It depends on the laws of your resident state. In most states the age of majority is 18. You would need to know not only the age of majority for your state but the compulsory education laws. It may sound ridiculous, but some states have laws which would require an 18 years old to finish a specified grade of education.
It´s 18.
Is it legal for a principal and counselor to meet with other than a parent or legal guardian about a student without permission of the parent
Not without parent permission. It could be considered kidnapping without that.
you have to be 14, in order to get it done without parents permission.
18 without parent permission
No the custodial parent has to have either the courts permission or the non-custodians permission.
No, in Iowa, a student must attend school until they turn 18 or graduate. A 16-year-old cannot drop out of school without parental permission.
No, a minor cannot obtain a passport without parental permission.
You have to be 18.
Nowhere.
If you are underage you need your parent's permission.
Without their permission they will have to wait until they are 18. The parents are still responsible for them.