My dd was only in school for one term, five years ago! But still I remember:
Always needing a backup plan for getting her there. If the ropy old car won't start one morning, who can take dd to school and bring her home again? If little sister's hospital appointment overruns, who can take dd1 after school? If little sister is too ill to go out, how can dd1 get to school?
Watching the clock obsessively from 7:30-8:30am and from 1-2:30pm every day in case I lose track of time and am late to take her or collect her. Planning nothing during those hours in case it takes longer than expected, or the bus doesn't turn up, or some other disaster might make me late.
Not being in a position to say, "It doesn't matter if you can't find the right clothes, or if they are dirty. Just wear something else."
Staying home in the evening so dd could be well rested for the next day. Having a lie-in the next morning wasn't an option.
Bringing home a previously-chatty child who now wanted nothing more than to go to her room and be alone after spending the day crowded in with so many other people. Trying to explain to my 3yo, who'd been missing her all day, that big sis didn't want to play now.