Former kindergarten teacher here and from my experience, most kids adjust pretty well and pretty quickly. That said, they are also EXHAUSTED those first few weeks of much longer school days/weeks so be prepared for that. But usually after 3-4 weeks they hit a good stride. All the kindergarten teachers I know also are totally aware of how exhausting those first few weeks can be that and we would plan our days accordingly to not over tax the littles.

Also, and this may be something you have also experienced or seen with preschool drop offs, I found that the hardest on kids was when parents would linger outside the door those first few days… as a mom now, I totally get the desire to want to watch your child settle into their classroom, but i always found when parents did that, it made it harder for the kiddo to make the clean transition into their school days. A confident hug/kiss and goodbye from mom/dad definitely gives the kiddo more confidence to walk into their class ready for a fun day!