A simple seed can muck up school menus and is banned from some campuses.
The website for Hallsville Primary School declares the campus is peanut free.
"Please be aware that we have students who are fatally allergic to peanuts," the posting reads. "This includes peanut butter, foods with peanuts or peanut powder (including granola bars), candy bars with peanuts, trail or snack mixes that contain peanuts and anything cooked in peanut oil or processed on equipment that also processes tree nuts or peanuts."
District spokeswoman Carol Greer said the campus-wide ban occurred after a new student with severe peanut allergies arrived at the Primary school.
"And when this was brought up, that we had a student (at risk) — that's it," she said.
It isn't only the public schools kicking out half of America's favorite P&J sandwich.
"We are a peanut-free campus in a sense," said Trinity School of Texas Director Richard Beard. "We do not use any nuts in preparation of any of our food."
The 33-year educator added an increasing number of children seem to be allergic to peanuts, possibly because of increased sensitivity or better public reporting.
The Food Allergy Initiative, a national nonprofit education and advocacy group, says the number of children in the United States with peanut allergy doubled between 1997 and 2002.
Symptoms of peanut sensitivity range from simple hives to life-threatening episodes of anaphylaxis that can cut off breathing.
"It seems to be more and more," Beard said. "We segregate children who have nuts (in lunches from home). They're only at one table in our (lower grades) lunch room."
There was a day when students who arrived at school without a lunch from home or funds to buy a meal were handed a peanut butter and jelly sandwich. That default meal no longer is an option, Beard said.
Longview allergist Dr. Jack Harris said peanut-free classrooms are not a bad idea. The nuts, and their dusty shells, easily migrate from one student's plate to the next one's skin, nose and mouth where its proteins do their dirty work.
"It's always the proteins that people are allergic to," Harris said. "It's never the fat part. ... Even getting a little bit in the mouth, that can be enough to kill you."
That's in extreme cases, he added.
"What we typically see is someone eats peanuts, and they break out in hives," Harris said. "They may have gastrointestinal symptoms ... (or) some hives around their mouth or face. Or, they may have hives all over."
Laura Lee Blanks, director of The Crisman School, said the Longview private campus goes a step further in guarding against food allergies.
"We don't allow gluten in our meals," Blanks said, referring to a protein found in many grains, cereals and breads.
Banning that allergen, which also restricts breathing and can be fatal, extends to peanuts in foods prepared at the Crisman campus. Students who bring lunch from home leave them in the office until lunch time, so any peanut-product lurking in a brown bag never sees a classroom, she added.
"We have some students who are just deathly allergic, so we don't allow peanuts in that classroom," Blanks said. "We have one classroom where no peanuts are allowed near, and we keep Epipens near because we know it can happen at any time."
Epipens are doctor-prescribed doses of the hormone epinephrine (also known as adrenaline), in easy-to-use devices.
"More schools are taking precautions," said Angela Huffman, a physician's assistant to Dr. Todd Holmon, a Longview allergist. "Some are going peanut-free. It's either being diagnosed more or more kids are developing sensitivities earlier."