Special assemblies will be held at the Newport secondary school on Wednesday and parents have been told that students will receive all the help that they need to deal with the tragedy.
Acting principal Ben Morgan said in a letter to parents on Tuesday that it was with great sadness that he had to report that one of two people who died in the incident on the A442 in the early hours of the day was one of the school's Year 8 pupils, Neve Cotgrave Hewitt.
"Another of our pupils has also been injured in the accident and is currently in a serious condition in hospital," he said.
"An accident of this nature and the loss of a young life is always deeply distressing and it is particularly painful when it happens within our school community. We understand that this news may be overwhelming and we want to assure you that we are here and will do everything that we can to support our families and community, our students and our staff."
He said that as well as the assemblies there would be other opportunities for pupils to discuss their grief and support each other.
"If you feel your child would be better supported at home during this time we will understand and fully respect your decision.
"As a close-knit community we want to ensure that we come together to support one another. Our school counsellor, student support team and other school staff will be available to offer assistance to students and staff members on Wednesday morning and throughout the coming days and weeks.
"We have also arranged for extra counselling support from the council's educational psychology team. We will be encouraging all students to talk to let us know if they need additional support or if they feel a friend is struggling.
"We extend our deepest sympathies to the student's family and friends. We are also sending strength and support to our pupil who is receiving the expert care they need in hospital. We wish them and their family the best."
Emergency services were called to the A442 at Wombridge, at the junction with the B4373, shortly after 2am on Tuesday, and found that a black Renault Clio had been involved in a crash.
A 36-year-old man and 12-year-old girl died in the single-car collision and two teenage boys, aged 16 and 13, were taken to hospital with substantial but non-life-threatening injuries.
Pc Craig Byle urged anyone who witnessed the collision or has any information or dash-cam footage of a black Clio travelling on the A442 which may help with the investigation to call him on 101, extension 7702085 or by email on firstname.lastname@example.org, quoting incident number 43i of September 5.