Welcome to the 21st century where schools of higher education have returned to deny parents access. Usually, the school will show a parent the clause that says once a child is 18 or enters an institute of higher education, he or she is given FERPA rights. The school will tell the parent that means the child has to sign a waiver before they can see anything! But checking the government website on the matter, you find that all that means is the child is now eligible to request to see the record and to file a request to have the record amended. Further down, the FERPA documentation states that parents for whom the child is a dependent do not have to have the child's permission to look at the record even if the child is over 18.
If you, as a parent, are filling out your child's FAFSA with your information because you are required to do so, that means the child qualifies as an IRS dependent. If you are paying at least half that child's support (and the child is in college), you can claim him or her on your taxes even if he or she is not living with you because that child is at college. Further, student scholarships and grants are not counted as the student's "earned" income. That means if your child doesn't have a good paying job while he or she is in school, you are probably supporting him or her. Now, I make no claims to being an accountant, a lawyer, or an IRS customer service person, so before you claim your son or daughter check with them to make sure the ever changing tax code hasn't done just that on this matter, but if you are able to claim your child as a dependent on your taxes, you can still have access to his or her academic record. The FERPA law does not say you have to claim your child for him or her to be a dependent. It simply says it uses the IRS definition of dependent.
The only way to change this policy is to begin reporting these colleges to the government. If your child is considered a dependent by the IRS (until age 24 for students), then you have the right to view his or her record without the student's written consent. Make a request in writing to see your child's record and keep a copy for yourself. And file a complaint if they refuse or require you to provide any further documentation than what they already have.