A zippy/fastener plastic wallet in their bag to put loose sheets/homework sheets in.
A little pack of tissues and some loose change in their bag.
There will probably be a parent log in for Show My Homework /Epraise/ClassCharts or whatever your school uses. Make sure you have it (or use your son/daughter’s log in) so you can keep an eye on timetable, homework, merits etc. Some year 7s struggle with being organised and need help at the start.
Pens! Endless supplies of pens! Having their own glue stick also speeds things up in class.
Photograph/ photocopy the timetable.
Teach them about sensible use of social media (if you choose to let them use it) and what to do if they’re receiving messages/added to a group they don’t want to be in/ how to be kind... so much of the school day is spent sorting these squabbles/things out.
Know their form tutor’s email and use it if there’s anything you’re concerned about or think school should know. My form are about to go in to year 11 now but I remember some of the mums in year seven saying they felt quite cut off because they didn’t see one teacher on a regular basis like they did in primary. The form tutor is that link, or at least it is where I am - I feel like I know ‘my’ families really well now.
Practise the journey.
Talk through what they will do if the unexpected happens, e.g. the bus doesn’t turn up, they leave their bag on the train, they get their period at school (spare things in bag?) etc. These are the things that can feel catastrophic in those first months if they don’t have a plan B.