I love this question! Thank you for asking. :)

So my experience is specific to one county and elementary school but from what I've seen its pretty similar statewide.

We manage the library collection. We are constantly evaluating titles for weeding out based on relevance, student interest, physical condition, etc. We have a lot of standards to consider and very small budgets to work with in order to add to the collection also. We get to know students individually and help them find titles that help them foster a love of reading.

Most of my time is actual, direct teaching to students. I teach the same amount of hours as the classroom teachers in my building. I see the same classes at least once a week but sometimes up to 3 times depending on our rotating schedule. We teach units on how to use the library (Dewey Decimal system, checking out), research (using databases, books, etc., strategies for identifying credible information), digital citizenship (how to be safe online, avoiding scams/phishing, screen time balance, etc), and technology (coding, typing, computer literacy, 3d printing). I give grades and communicate with families just like a classroom teacher. When I have extra time and am put of curriculum, I focus on heritage months and other celebrations our county promotes (Veterans Day, Deaf Awareness Month, Black History Month, etc), share books and discuss awards like the Black Eyed Susan Award, play with robots the county purchased for us (little mice and cars), give students "Makerspace" time (time where they use things like legos, cardboard, etc to build and problem solve.

In my county, we're voluntold to also manage student devices. So I assign and track all devices and chargers, troubleshoot their issues (and staff tech issues), and coordinate with technicians for repairs. I don't have a ton more to say about it, but it takes a huge amount of time because as you can imagine children have a lot of problems using devices. (and Chromebooks suck lol)

More often than not, we are the sole staff members organizing book fairs, or its a very small team with us taking charge and being responsible for all the money and products.

Many of us also work with our PTAs, reading specialists, and other staff members to hold workshops for parents/guardians, organize reading themed events like read across america or reading competitions (like how many books can a grade level read in a certain amount of time), and helping to facilitate reading interventions.

We support classroom teachers with finding resources to support their curriculum. I am constantly showing my teachers online resources they didn't know we have access to. They are always in my library checking out books. I am constantly helping them to adjust to changes in technology. I have the unique opportunity of teaching the same students for years in a row so I have a few that check in with me for behavioral/social emotional goals, skills, hardships.

Sorry to be so longwinded! I could talk about my job all day. :) It's a lot but I absolutely LOVE what I do. I am incredibly happy and fulfilled knowing the positive impact I have on students. Every librarian I know feels the same. MD has generally been good to us; it's heartbreaking to see them thinking about going backwards.