Elementary math notations per culture or country I cannot find a place listing the mathematical notations per country. The symbols listed in wikipedia refer to english notations. (Even the french page for instance, reproduces the english symbol for parallelism).
This question is very similar but the answers focus on maths at a university level, I am looking for elementary maths symbols only (from wikipedia: "topics frequently taught at the primary or secondary school levels").
As a complete answer might be too long, I suggest each answer to focus on one country and to only highlight the differences with english notations (but maybe there are more efficient, better ways to organize the answers, maybe a community wiki would be appropriate?).
I start with french and will update the answer when I find out more differing symbols.
Last note: this should not be limited to symbols used "in line" but can also list symbols used on figures (like, for instance, right angles that are not marked/decorated the same way by german people as by english or french people)
 A: Russian mathematical notation or peculiarities of Russian notation in mathematics:
$English \;-\;Russian$
$3.14 \;-\;3,14\;\;$(in Russian, dots are not used for decimal fractions)
$1,000,000\;-\;1.000.000$
$\$100\;-\;100\$$
Point $A(1,2) \;-\; A(1;2)$
$tan\,x \;-\;tg\,x$
$cot\,x \;-\;ctg\,x$
$sinh\,x \;-\;sh\,x$
$cosh\,x \;-\;ch\,x$
$tanh\,x \;-\;th\,x$
$coth\,x \;-\;cth\,x$
$sin^{-1}\,x\;-\;arcsin\,x\;$ (and so on for other inverse trig functions but the general sign for inverse functions is exactly the same e.g., $f^{-1}.\;$Note that we also use $arcsin$ etc. in some UK/US books like those by Serge Lang. It's also used in other languages and universally understood). Yet something like $arch\,x$ may look arcane but it is not if you look a few lines above.
${{n}\choose{k}}\;-\;  C_n^k\;\;$ (it is backwards!)
$P_{n,k}\;-\;  A_n^k\;\;$ (backwards again)
(And $\;m!\;$ as permutations is the same in Russian: $P_m$)
In elementary algebra (not complex variables):
$log\,x\;-\;lg\,x\;\;$(common or decimal logarithm with base $10$)
In geometry everything seems to be the same (all symbols, denotations etc.) but area is never denoted by the letter A, it's denoted with the English letter S. Volume, however is similarly denoted by V. 
Long division looks weard--google the Russian words 'деление столбиком' and see all the pictures! Also, note that letters A, B..., a,b,c... are pronounced like in Latin!
Although it looks like there is some significant difference in notation, it's not the case. Almost everything in all math branches looks exactly the same when compared with Russian texts. So much so that it is difficult for me to come up with some other differences. I can, at a push, say things like: In Russian books parabola is always $y^2=2px$ instead of $y^2=4px$ but you can come up with various subtleties from book to book. Simply put, notation may slightly differ in various Russian books as it may also differ in some English books. And there are even fewer differences in notation when it comes to higher branches of mathematics.
A: Notations differing in french:
\begin{array}{c|c|c}
  \textbf{Theme} & \textbf{French} & \textbf{English} \\ 
 \hline
  \textbf{Angles} & \widehat{ABC} & \angle ABC \\ 
 \hline
  \textbf{Distance} & AB & \overline {AB} \\ 
 \hline
  \textbf{Lines} & (AB) & AB \\ 
 \hline
  \textbf{Numbers} & 1,23 & 1.23 \\ 
 \hline
  \textbf{Parallel lines} & \newcommand{\frparallel}{\mathbin{/\negthickspace/}} (AB) \frparallel (CD) & AB \parallel CD \\ 
 \hline
  \textbf{Triangles} & ABC & \triangle ABC \\ 
\end{array}
EDIT: the source for french notations is myself, as I studied maths in France from school to university and am now a french maths teacher (in France). Nevertheless I can provide examples. There's an open source maths book for school where you will find these notations, like here for lines, the next page for parallel lines, and there on the left you'll find notations for angles.
