My daughter's school doesn't allow students access to any medications, not even in their own backpacks. I have to leave my daughter's inhaler with the school nurse, who of course is trained and knowledgeable on how to treat an asthma attack, as well as other medical emergencies.

At the early learning center I work at, there is a peanut and all-nut ban due to allergies of some students. It's really surprising how many children have a variety of different allergies. Some to milk, egg, nuts, green beans, wheat, soy, strawberries, cherries. Each classroom keeps a list of which students are allergic to which foods to ensure they are not fed those foods during meals/snacks.
I was told a story about how one child's mother accidentally left epipens in the child's backpack and that child got into their backpack during the school day, after putting some art in there to take home, and tried giving the epipen to themself, but didn't press it all the way, so it got stuck in his finger. No one could get it off his finger, and his finger swelled up. His mom came and took him to the emergency room where it was removed and he was treated properly. That is just one example of the many dangers of children being given access to medications. One of the reasons meds say KEEP OUT OF REACH OF CHILDREN right on their labels. Because children are not mature enough to be safe around medications.

I think a blanket ban is perfectly reasonable, especially for an allergy as serious as peanuts. Luckily I don't have any life threatening allergies (just some not life-threatening ones) to anything as common as peanuts. But for some people, even being in the same room as a peanut can kill them. I don't know how they live with it.

Also anyone who says it's not fair,. is it fair to the person with the allergy that he/she has to die just because you want peanuts? Anyone who says people can't afford something that's not peanut butter then those people probably qualify for free school lunches anyway.

P.S. All this talk about students not being able to carry epi-pens and such on them makes me wonder something. Does anyone know what they do at big campuses (like a large middle school) where there is never going to be enough time to run to the nurses office and back?

There's nothing unreasonable about that. I sure wouldn't send my kid to school if they were deathly allergic to something not banned at the school. The kids are in the school's care when they get there until they leave to go home and they can be held responsible for injuries or deaths.
If your kid REALLY can't get through the day without a peanut butter and jelly sandwich, give them one for breakfast or pick them up for lunch and eat in the car with them. If your school allows that, my elementary school did.
It's not that big of a deal.

I think so, it might seem over protective, but when you think about kids sharing their lunches with other kids and stuff...

I would like to point out that you can also freeze juice boxes/yoghurt to act as a ice pack- that way food stays nice and cold until lunchtime and you have nice cold juice to enjoy or put food in a insulated lunchbox, which is about £15-20?. Ice packs aren't that expensive anyway.

I always had cheese or cheese and pickle sandwiches or sometimes cold pizza or chicken nuggets. Not the healthiest but yummy. My mum didn't think peanut butter was a good filing for a lunchtime sandwich

I remember in elementary school this was this problem, so what they did was they made a "peanut-butter free" table where kids with peanut butter allergies had to sit. Friends could sit with them but they could not have any peanut butter in their lunches. Also nobody could share/trade lunches with each other, no matter what they had. While there are a few minor flaws with this (ex. a girl wants to sit next to her best friend at the table but her mom makes her a pb&j sandwich for lunch almost every day) I think it's a much better alternative than banning it outright.

If you don't mind me asking, what would they do when they have someone who is so severely allergic they cannot even be in the same room as a peanut? The system you described seems pretty smart but I can't get this one flaw out of my mind.

With such a severe allergy it would be only logical for them not to be put at such risk at all and be in a truly controlled environment like their own home. Trying to implement a completely peanut free public school (for that matter private school since it boils down the same) is virtually impossible. It's not like they have ways to scan for peanuts like metal stabbing and shooting implements.

(Big As(Funnily enough there are still boatloads of dangerous weapons that don't have any metal in them whatsoever. And there are even more things native to the classroom setting that can be used as a makeshift weapon. The fact of the matter is no one is particularly concerned that a kid is going to completely flip his shit and start beating people to death with an outdated biology textbook. Because kids aren't that creative or desperate enough to go that route. Because almost all school shootings were based on a pathological want to appear cooler than they are. That's the real reason. You see inmates do a lot crazier and inventive things because they are that desperate. School is nothing like a prison, kids just like to be melodramatic sometimes and put bullet holes in other kids because they have poor impulse control and a bone to pick with anyone who they think are out to get them. And that's really all there is to say on the subject.)s Tangent).

tl;dr
Allergens aren't like guns. They can get everywhere even without you being able to see them.