This “fight or flight” mechanism is built into all humans, but is oddly absent from those in positions of power, making them better leaders and/or teachers. As teachers, popping balloons is as natural as using present perfect tense to describe life experiences, yet many students become uncomfortable after several balloons are popped in the classroom.
To lessen the fear that the students exhibit, forewarn them of the balloon popping so that they may mentally prepare themselves. Students do this in a variety of ways, whether it be plugging their ears, tensing their jaw muscles, focusing intently on the balloon, or asking questions related to your motivations.
A great way to move past the irrational fear of popping balloons would be to allow the student to pop a few themselves, under the supervision of the teacher. With the side of the balloon closest to the student (to avoid blowback), have them lightly insert a sharpened pin into it, bursting it. This may be repeated for every inflated balloon in the classroom.
As always, be respectful of the student’s needs.