I heard there was a law that allowed parents to attend a childs first day of school and graduation. Is this true and if so how would one go about finding that law to see with my own eyes?

There is no such law.

SOME states (Massachusetts is one of them but unless it has been signed into law quite recently New Hampshire is not) have a law that a parent must be allowed x hours of unpaid time to, among other things, attend school activities. The MA law, which is probably what you're thinking of where you're in a neighboring state, is called the Small Necessities Leave Act. Other states which have such a law may call it something else. But, as I said, unless it was signed into law in only the last couple of years, NH does not have one.

New Hampshire has a "small necessities" leave but it does not apply to taking time off to attend "school activities." It only applies in certain circumstances to employees who are crime victims, employees who are emergency response individuals (ie member of fire dept.), and employees who are certified by the American Red Cross as a disaster relief service volunteer.