Keep in mind that Spring Break hangover is a thing. Especially if you teach junior high and/or non-varsity. For me, it hasn't been a lack of interest, it's more about shaking the rust off.

In my region, non-varsity junior high bands go to contest the week after Spring Break. It doesn't matter how much I try to prepare them or warn them, they always come back from break sounding like butt and then entire week we're trying to get back to where we were before break and hopefully a little bit better by Thursday or Friday. It's stressful. If we went a week later, it would be easier.

Just be aware that it's a thing that happens with young bands/musicians and know that it's not going to be good immediately after the break.

The good news is, they are capable of recovering fairly quickly.

As far as interest, just make sure you're not peaking too early. And you get more experience, you'll figure out how to time it so the band isn't maxing out their performance ability prior to UIL. That's when disinterest occurs, when the band has peaked, isn't getting any better, and it becomes stagnant and just doing the same thing over and over with no discernible progress.