Chinese Visa from UK

We are a school party of 3 adults and 20 children aged 15-17 years old.
We are visiting China in September 2024.
We would like to organise the Visa by asking each pupil to fill in the online application form then escort the pupils to the office in London with the required documents and fingerprinting etc. However, the parents will not be accompanying the pupils. Would we require any other documents and do we need to make an appointment ?