Peer Reviewed Journal via three different mandatory reviewing processes, since 2006, and, from September 2020, a fourth mandatory peer-editing has been added.
Before 1970 both foreign language and mathematics were hard to learn because the two taught grammar before language. Then a turn took place in foreign language education allowing students to learn it through communication. Mathematics education never had a similar turn, so it is still hard for many. Therefore, this paper asks if it is possible to learn mathematics as communication. We see that three different kinds of mathematics are taught, pre-setcentric, setcentric and post-setcentric. And that the three grand theories disagree as to which to recommend. Being inspired by the fact that children communicate about the physical fact Many with two-dimensional box- and bundle-numbers with units, a curriculum is designed where trigonometry is rooted in a mutual recounting of the three sides in a box halved by its diagonal. So, the answer is: Yes, core mathematics can be learned as communication about boxes since it is directly connected to counting and recounting Many in boxes and bundles.