Routine routine routine, it is the only way to get through it all!
It works in my house, I have an "organisedmum" diary so all the school stuff is clearly marked already on next years calendar.
Name tapes are iron on so they can be put on when ironing the uniform if any have come off.
He has school dinners that are paid for termly so only have to remember that one cheque.
Get them up 10 minutes before breakfast (I have a 6yr old about to start yr2 and my 3 yr old is about to start preschool, I am a sahm) breakfast at 7am. Get dressed at 7.30 and brush teeth and hair.
TV is allowed on at 8am and goes off a 8.20 (end of program) for shoes and coats on to walk to school.
PE kit lives at school
On return, change out of uniform, read book/do homework and learn some spellings. Playtime until tea. Meals are planned. All sit down for tea together. More playtime. Tidy up, bath, teeth brushed, story, bed.
Nice evening for me and dh after shoes polished and coat wiped down from football mud splats glass of wine, MN, TV, book, whatever takes my fancy.
All housework/shopping is done in the day as I am sahm.