In Israel near schools, instead of this thing, before and after the learning day in a grade school, there are several students that wear yellow glowing sweater near the pedestrian crossing that blocks the road with a STOP signs when there were students that want to cross. There is also signposts that warn that there is a students in the way and also a limiting speed sign and road humps.
We also have students for Elementry school ONLY that either wear bright orange or greenish yellow cross belt with a badge on them and do pretty much the same thing......also we have signs like this above pic, but often is found on side of roads in Maryland instead.....the student that wears the belt are always in 5th grader and are called "patrols"
I've never seen one like this one here in Ontario before, we also have sign that does the same thing but ours are pole mounted and a blue school zone sign on top with a "Maximum xx km/h when flashing" sign below the school zone sign. The flashers are on the side of the two signs and flash like a railroad signal.
our Modern Ones are typically mounted on Large Steel Poles with Long Steel Arms that Extend Partially over the Road...much like a signal Pole....it will have Two Yellow Signals on it with a Square Yellow sign that says School Zone also listing the Speed limit Which is 25 MPH for our School Zones...or other times its mounted of a Fairly Short Pole...with the Sign in between the Two Signals which are on the pole itself....they always Flash in a Wig Wag Pattern...which is like you said...like a Railroad signal....we dont have any like this in my area either...but this town has alot of Old Stuff....lots more than Tyler.
Rhode Island used to have soemthign like this , but those are dying off in favor of these with no lights. The older flashing weren't reflective and the newer ones are on a green U-channel pole and are reflective.