I asked office and had a call from teacher today saying my son wouldn't need games kit tomorrow as not timetabled games/sport, and sports teachers wouldn't expect boys to have kit with them tomorrow on day 1. DS is in yr6 at W. Though they might want trainers at least to try out few things at lunch time/have a kick around.
That said he did yr6 there last year and left his sports kit in locker, most of books left at home.
And yes when they have swimming, they will need a towel, but can just bring towel and trunks to school that day and hopefully home again!
Not sure if same this year, but last year whites for PE (generally indoor hockey, basketball, raquetball) or swimming (for one half term) and blues for games, ie rugby autumn term and hockey spring.
hope they all have fun tomorrow.