Katherine Elizabeth Greatorex, from Darton, Barnsley, suffered from a rare disease called Kawasaki which led to heart failure. She was a pupil at St Thomas a Becket Catholic School in Sandal.
Just before midday on Friday she collapsed during a PE lesson and was rushed to Pinderfields Hospital were she was pronounced dead. Later that afternoon pupils from years 7 to 10 and staff were informed of her death.
The school's priest was in school as well as its Catholic Care social worker to offer help or support to staff and pupils. The school chapel was also opened.
Coun Wayne Jenkins, cabinet member for children and young people at Wakefield Council, said: "Our thoughts and prayers are with Katherine's parents and family at this sad time, as well as with the wider school family.
"Support and help for all those involved in the school has been made available through the church, Catholic Care and the local authority."
St Thomas a Becket Catholic School has 770 students on its books.
For a full tribute to Katherine and more pictures, see Friday's Express.