A school principal is hired to take care of the school and its students. It is assumed that one of his qualifications is to be level-headed and think thoroughly about school problems. If the principal has reason to believe a student in his school has a bomb, the benefit of the doubt should be given him. He should have the right and be allowed to call the police before calling the parents, especially since if the threat is real, it would harm a large number of people.
If a child is suspected by a principal or any other member of a school's administration the school employee should be able to phone the police or proper law enforcement department without prior consent or notification of the child's parents. Schools being private or public have to look out for the safety of more than one student. If someone was suspected at an airline or bus station for example, security there would investigate. Because schools have no security type employees in most cases the police would be the first line of defense. The right of the parents to know has no relevance to whether or not a principal should be able to call the police because he has to look out for the entire school -- employees and students. As a citizen he has the right to phone in suspicious activity.
High school principals should be allowed to call police when a child is suspected to have a bomb. This is because security comes first. A bomb can go off at any time. What can a parent do about it. Police can get the bomb squad to check it out, perhaps in time before one would go off.
No, a high school principal should not be allowed to call police on a child he suspects to have a bomb without first questioning or notifying the parents. Unless there is an active situation in which people are being harmed or are about to be harmed, there is no reason to call the police on a child without first notifying the parents of that child. In the case of the Ahmed Mohamed, the teen from Texas who was arrested after bringing a homemade clock to school which teachers thought was a bomb, he was interrogated by police without the presence of a lawyer or even his parents. In fact, the parents were not even aware their son had been detained until the police - not the school - called them to report that Ahmed had been arrested. It is unfair and unjust to jump to such conclusions in the first place. In the second place, it is irresponsible of a school official to not report to the child's parents that the police are becoming involved with the child's activity.