My twins turned 5 in December and today is their first day of school. It’s pretty quiet around here!
In England the children start school in September - I hope there were no tears on either side!
I used to teach primary school. It was a bit of a job helping to console the kids on their first day, but a much bigger job consoling crying parents. 
It’s not just a big transition for the kids. Enjoy your new found freedom!
They grow so fast! I assume that they were not as sad as other kids (if any) because they have each other 
Yes, if the school lets them be together it should be a big help to them. A big “milestone” for the family.
I don’t remember my “first day”, but I remember getting on the wrong bus home once in kindergarten. The only bad “first day” memories are of the horrid “new clothes” that made my mom proud but that I was overly self-conscious of. Not as bad as getting a “new haircut” that some poor kids were inflicted with getting but a bad enough beginning each school year.
Starting what for you would be mid-Summer seems like an odd time to start. How long is the year? I think here it’s around 185 days.
Bet it wasn’t when they got home!
I remember mine quite clearly. I was a couple of months short of my fifth birthday, and I was desperate to go to school. My big brother had cried every day for about his first six weeks at school, until they’d moved him into a different class. (The first teacher was rather deaf and shouted, which frightened him.) I think they were expecting me to be as bad, because they put me in with the other teacher from the start. I was, as ever, accompanied by my faithful teddy bear. Mrs. Holmes explained that there was a special shelf where he could sit until playtime with the other toys, and I drew myself up to my full two-foot-six, or whatever I was, and informed her that he wanted to stay with me. She rather hastily agreed that he could, since it was his first day, but that I would need to explain to him about sitting on the shelf if he wanted to come again tomorrow.