By any other name would smell as sweet."
Romeo and Juliet (II,ii,1-2) by William Shakespeare.
Memorizing your students' names quickly is respectful. And using their names to redirect their off-task behavior ( e.g. "Joan, sit down please") is much more effective than giving directions to 'everyone' (e.g. "Everyone sit down. Everyone sit down please. Please have a seat. JOAN! Sit down!") You should have just started with "Joan, sit down please"
I don't care how bad you are with names, because you are going to have to remember 3,000 of them or more, in a 30 year career. And twenty years from now, when that former student of yours runs into you at the grocery store you'll be expected to answer the question "Remember me?"
The real reason to remember names of course, is that our names are music to our ears, and they can't be said aloud without us hearing them. If someone says your name, you're all ears. And if someone remembers your name quickly, you like it. There is nothing quite so effective as using a student's name, no matter the occasion. And there is nothing worse than not remembering it because that sends a message too: You are not special and you don't matter to me.
So here's a tip: Get last year's yearbook, and start memorizing names to go with faces. That way, when a student who is six inches taller than you are, with a swagger that would make Idris Elba look like a wimp, walks in the door on the first day of class, you can say, "Good morning, Robert." It's hard to over-estimate the effect of that simple statement. You just told Robert that you know him better than he knows you. And you have told him that you care enough to have learned his name before school starts. And you've told him that you know things....that he didn't expect you to know. He might decide to give you a day or two of his best behavior.
If, on the other hand, you say, "Good morning, See-Oh-Bahn", because you practiced sounding out "Siobhan" from the class roster you got the day before - you're toast. Because it's pronounced "Sha VAWN". And Siobhan (did you really just read SeeOhBahn?) is not likely to forgive you, or to feel good when the rest of the class laughs at your massacring of her name, which everybody (except the hopelessly clueless teacher) knows how to pronounce. I know this, because I was one of those kids who knew the teacher would mispronounce my name. It wasn't an easy name and I knew that. It is mispronounced more often than pronounced correctly. I now go by my middle name. A teacher who could pronounce my first name had my instant gratitude. That's a good thing for a teacher to start off with.
So, if you have no yearbook, but do have a roster, take a few minutes to go find a couple of veteran teachers in the grade before yours and get them to tell you how to say the students' names correctly. I'll write a different post about why it should be a veteran teacher you talk to.
Knowing kids names and saying them correctly on the first day, can make or break your introduction of yourself to your new students, and potentially give you a respectful foundation on which to build your relationships.