See the article here.
I thought I would aid understanding by translating the comments by one parent:

Sixth grade parent Kelly Adams told ABC News affiliate KAIT8 that the request to take prayer out of the opening address upset parents and students, explaining that the school’s decision to cancel was justified because “we just want to take a stand for God because we felt like out rights were taken away.”"we just want to behave like a bunch of pissants because our self-given privileges to ostentatiously push our religious messages to everybody were being threatened".
Conceding that not everyone is Christian at the school, Adams added: “I realize they have rights too but you can’t take rights away from one group and give it to another.we weren't going to abandon our entitlement-ridden mindset for those Godless...people”
Kelly, along with other parents, have arranged to hold an alternative ceremony at a nearby church, where they will be free to pray. ”We are including everyone, everyone is invitedWe are desperately hoping that the Godless jerks take the hint and don't show up, we want everyone except anybody whose religion we find inferior or non-existent to come and be a part of it,” she said of the decision to relocate.
“We’re not trying to be pushy or ugly to anybody, we just want them to know there is a God who loves thembut we cannot stop behaving like a bunch of entitlement-ridden petulant exclusivist little shits,” she said of the new ceremony.