I bet it was not standards. I bet it was not a homework assignment(unless it was one that scarred you for life).
I bet you remember favorite teachers. Teachers that made you feel important. Teachers that made your voice feel important.
Or maybe complete opposite where the teacher was beyond terrible.
Either way the memories are the memories that left an emotional impact in some capacity. It was not the day to day jargon of history or science or five paragraph essays.
Remember that when working with students. Are you creating those memories to provide students with learning experiences they will never forget? And more importantly, are they the memories students want to keep?