I have to deal with this all the time with Little League. An official birth certificate MUST have either:
1) A raised seal
2) An official stamp (and must be the original, not a copy)
3) Printed on special official document paper (and be an original)
A notary would be useless. They can only attest to whether a signature on a document is yours, they can not make an unofficial birth certificate offical.
An easy test is to take the birth certificate to the closest Post Office that handles Passports, they can tell you in an instant if this is an official Birth Certificate.
Speaking of Passports, they are the BEST proof of birth. The only time our birth certificates are ever out of our sight is when we renew our Passports. We use the Passports for school/little league/soccer and travel. They are durable, and an official document, and so our Birth Certificates don't get beat up. I can't tell you how many badly beaten up Birth Certificates I have had to examine for Little League. Some have gotten wet, others the kids have drawn on the back with crayons, others look like the dog ate them.