I'd strongly advise against removing this code. Not providing hyperlinks to the teacher's direct extensions is a significant roadblock to efficient usability of this portion of the website.

I'll use Tina Cassiere's information as an example. I can update the phone link creation function to automatically convert "Room 105 | x2105" into a link on "x2105" that has an href attribute of "tel:+1-513-389-3242;2105" that will dial the school's phone number with the extension. This would get a caller directly to Ms. Cassiere's direct extension without forcing them to navigate the phone system.

This wouldn't take too much time to code and test, and it would have significant improvements on both usability and efficiency (after all, I'm guessing a parent will be more patient and reasonable with a teacher if they don't have to spend five minutes navigating a phone system before they can reach the staff member they're trying to reach).

As an additional reference on this topic, please see item 4 of the following link.

https://neilpatel.com/blog/mobile-design-best-practices/

They don't want to pay for the added field, even if it's a $5 cost. And if we do it for free, then they'll be like "well why can't you do xy&z for free?"
But they do want the room number to be visible

So you can make a choice from there. 

It'll be faster and easier to just add an ACF field for the room number.

*sigghhhhh* 
ok do it

This is updated and will work correctly as soon as someone finishes moving the teachers' room numbers into the correct places.

I've updated the ACF fields for Administration and Kindergarten for testing purposes. They'll need to move the rest of the content (or they'll have some really annoyed parents).

Here are some important points.

For example: Ms. Cassiere is in Room 105 and has extension 2105. This will only work correctly if (as I've done) someone enters 105 into the Room Number field and x2105 into the Phone field.

Problem with this is some of the Rooms are "Gym" or "101A" "206B"
Didn't seem to break anything (see Kathy Wissel under Content Area Specialists category)

Just stack the room below the phone when it displays. 

The word "Room" won't be inserted unless a room number starts with a number. Thus, entering "Gym" in the room number ACF field will simply output "Gym" (rather than "Room Gym").

I've also removed the line after the room if the staff member doesn't also have a phone extension.

The only remaining issue is that the staff page treats a room number without a phone extension as a link to "tel:+1---", which won't break this page or do anything other than mildly annoy someone at some point. Fixing this would likely take 30–60 minutes.

As this is a non-crucial error, I'm marking this task complete for now.