I have two things to consider before you do anything else:

* Is there a music teacher floating around there somewhere? This almost certainly should include them.

At my parish, I pick the music (as DoM) and accompany, and the music teacher (current one fresh out of college) implements it. The principal's orders are to plunk one grade per week (going down to 1st, which, incredibly, has mostly worked) in the choir area, so that's what we do. I started there in 2021, and we had to start over on hymn repertoire, because the kids forgot everything during Covid. Four years (and two music teachers) later, the kids are singing antiphons and a good chunk of traditional stuff, and not doing too badly at it.

* How close is your leave? If it's relatively soon, tread water a little while and start the process when you get back. You do not want to have to start, then stop, then start again on something like this.

Just a thought, because we're in transition right now too at the school so I've been thinking about this a lot recently: Are the classroom teachers able to put on music while the kids work? And if so, can you provide them with a "play list" of the music you want them to learn? That way, they are somewhat familiar with the tune/words when you go to teach them.

Our school has a "morning song" which is played right after announcements/morning prayer. Right now it's all P&W, but the music teacher has been dovetailing it into Mass music. When I was accompanying for them last week, she reminded them a few times that they heard it as a morning song several times this school year already (we have lots of new kids in our school things year, so the music is new to a sizeable number of them). It helped a lot once she reminded them of that.

Is there a music teacher floating around there somewhere? This almost certainly should include them.

There is, but she's only part time and trying to do a normal state curriculum. I did have a chat with her today, and it turns out she is catholic and she's interested in possibly including a few liturgical things. I'll be relatively limited in what I can send her way, but she's willing to do some things in this regard, which is a delightful surprise.

How close is your leave? If it's relatively soon, tread water a little while and start the process when you get back.

That's the plan. Wife is set to be induced for #4 next Thursday... (send an ave or two our way, please!). Knowing this was coming was largely why I did not rush to try and establish something the first few weeks of school; it seemed unwise to start something, only to then recuse myself from it for over a month.

The principal's orders are to plunk one grade per week (going down to 1st, which, incredibly, has mostly worked) in the choir area, so that's what we do.

This is a completely different approach to anything I had considered previously, but there's a certain genius in it... you'd be able to inculcate the idea that we are all responsible for liturgy, and for participating and singing, in the entire school, which I'm sure pays dividends even when the kids aren't up leading the music. I'm going to have a think on this. A good think indeed.

Cantors sing together in groups of 2-3, never alone.

We used to do this at a previous gig (although we only went up to grade 5) and I'd have 4 "cantors" and between the four of them, they often made half of one normal person's sound. I think they were just too little.

partner program pairing up older and younger students who sit together at Mass

we have this too. I do wonder if I end up going down to 4th or 5th grade whether or not I should establish a similar buddy system just for the choir itself.

Marian antiphon as recessional

I desperately want to do this... we did it at my last parish, and after 2 years of school masses, the entire school (pre-5) could sing the Salve Regina from memory, and it was quite moving. They did it very well, too. I'm going to have to wait on this one at least another year, I think.

Are the classroom teachers able to put on music while the kids work? And if so, can you provide them with a "play list" of the music you want them to learn? That way, they are somewhat familiar with the tune/words when you go to teach them.

I've debated this. I'm not sure how well it would be received; in all likelihood, it would only be one or two teachers. The teacher who used to direct the choir is very big on music in their classroom (which is why so many people are upset that it appears that I drove this person out) and they have their students sing multiple times per day. Honestly, while they are teaching music I would otherwise tend to avoid, it's outside of mass so it's largely fine, and I think they are doing the entire school a BIG favor by inculcating a culture of singing among the younger students. A few more years of this cycle, the entire school will have gone through this person's classroom, and that will be a real win. They are now coordinating a Monday morning hymn sings after announcements. I'm not touching that with a 10' pole. I say: have at it, and we are all the better for it. I want to avoid appearing to encroach much more upon the school... I kind of want to let that be their territory. Teachers do the school thing, I do the Mass thing... We'll see. But I'll have to tread lightly there, too.

With your limited rehearsal time, mastering a setting of the Ordinary would be a good place to start.

This was my thought too.

I would skip singing responsorial psalms, or just sing them yourself.

I'm singing them myself at the moment; I composed a whole semester's worth that are essentially a setting of the same basic tonal contour that I made up myself. I'm hoping the older kids will do a better job than the littles did at my last parish... I really do not want to go back to reading the psalms. This is a sore point for the admin (I'm "taking something away from the kids" — as though they have the right to read, esp. when the missal specifically instructs that the psalm should be sung wherever possible. It's very possible with a full-time, professional musician! lol.). In an effort to olive branch the shift from student-read to [hopefully] student sung, I offered. 1.) the psalms could still be read by students for all of Advent & Lent, 2.) to work with student cantors, & 3.) if necessary, we could do the hybrid model where only the refrain is sung, but the verses are still read, after which a brief intro is given and the refrain repeated. All of these were rejected... but I feel very strongly about the singing part. For starters: singing is a memory aid. The little kids never remember the response well when it is spoken. But they do better when it's sung, even if everyone isn't singing. We'll see where the dust settles. I will have to experiment based on which kids show up.

we are rotating through...

I've thought about doing this too. There are a few eucharistic hymns that I cannot do away with, but I just introduced Sweet Sacrament this last week. I intend to repeat it very regularly until they know it well. At my previous post, I used to make monthly worship aids with "hymn suites" where we would repeat the same 4 hymns every 3rd week or so, which allowed me to reinforce hymns that were still in recent memory. That idea was shot down here last year. So I have to program each mass as it's own, albeit from their core repertory. I'm trying really hard to be respectful of what they've already been taught, and not just change everything overnight. This includes continuing to schedule a myriad of things I have no interest in teaching the children... but I'm trying to be gentle.

My problem was, the diet was so nutrient poor, that we were singing things like "Alabaré" 3x a year, but never once singing "Holy God We Praise Thy Name". And when I first got here, it was accompanied to a casio keyboard pumped through a guitar amp, meanwhile we have a literal million-dollar organ. It was pure folly. Just even going organ-only with their current repertoire was a major shock for some. That was one area where I wouldn't (couldn't) budge. But that's also why I spent an entire year completely hands off and merely showing up to accompany as appropriately as I could, even when the repertoire was completely opposed to the organ. I just made the best of it. So we are now into my third school year before I've attempted any more changes.