I'm only counting "Western Europe", excepting the former East Germany, west of the old Iron Curtain for a whole bunch of reasons.
Where do you get 85 school shooting deaths (?) in this century? VT 32 + Newtown 24 = 56. (In all cases I do not count the shooter if he died.) Plus I'm also pointing out that there were a lot more school shooting incidents.
It's too late for me to go into spree shootings, but ... when I just added up the deaths for Europe from my list, I got 157.
I just output the wiki lists it appeared you were working from. Once you start selectively editing you open yourself up to acts of cherry picking so I didn't edit anything. It's possible that I missed string entries that didn't follow a sort on the date column, I'll take a look again later but here is my list for us school spree shootings this century:
Fair enough on the US side, although your addition on others still looks to be off, e.g. I get 53 for European schools, and you still haven't addressed the 157.
But arguing over simple body counts reeks of Vietnam War insanity; that Europe is not doing well in this is undeniable, worse or not is a debatable point, the statement that "Everybody in Europe manages just fine without owning guns..." is obviously falsifiable in every particular, i.e. they have lots of guns and they misuse them as well.