Lucy-Ellen Revell, who already holds a Jack Petchey Award for her community work, will be collecting her latest honour today (Thursday) at a ceremony at London's Canary Wharf attended by music legend Robin Gibb of the Bee Gees and Childrens' Commissioner for England, Sir Al Ainsley-Green.
Lucy, who is also a hard-working member of the Blackwater Judo Club, was nominated for being an outstanding carer while being so helpful to others at school.
Lucy is one of three students from the Plume School, Maldon, who will be collecting their awards today. The others are Chris Adams and Chelsie Knight, both 18 and sixth-formers.
Lucy of Wood Street, Heybridge, said: "It came as a bit of a shock to be told I was getting the award. I knew I was being nominated but I didn't think I was getting it."
She added: "Mum is very proud of me. She is going to be there and she is getting a new outfit to wear."
Lucy gets up at 6.30am to help get her mother's breakfast before heading off to school. She does her homework in break times so she is able to help out in the evenings when needed.
Her mother Kelly Revell, a single mum, developed an auto-immune deficiency after being stung by a wasp in 2003, has difficulty standing and uses a wheelchair.
She has also since been diagnosed with multiple sclerosis.
She said: "She does do so much for me. I am really, really proud of what she has achieved."
Head teacher David Stephenson said: "It's quite an achievement to be recognised by a national award. Our school gets local recognition and this takes it into the national arena.
"It is also quite an achievement for three students to be recognised. It shows a commitment to the community and the wider perspective of students."
Maggie Turner, chief executive of the Diana Award, said: "The impact of the Diana Award is immense and young people carry this lifetime honour with pride and a sense of duty as active citizens for the rest of their lives.