We're planning to run the project for first two grades of the elementary school kids, in which we want to facilitate the spatial thinking development along with the regular arithmetic course and make it easier for them to get into advanced math in further educational levels. What would you recommend to start with and which well-recognized and trusted textbooks, approaches, methodologies, and quizzes do you know what may ease this task?
We're located in Moscow as a company, but going to work way beyond the region, besides, anyway, I wanted to make sure it's possible in general for the considerably early age (6-9 y.o.) from the psychological point of view, first of all, without binding to the local realia of the region.
There are two disputable articles I've read up to the moment in this direction: https://www.researchgate.net/publication/313588375_The_Development_of_Spatial_Skills_in_Elementary_School_Students http://ling.umd.edu/~jlidz/Teaching/F05Seminar/feigensondehaenespelke04.pdf
Also, I checked the OECD report about the early STEM preparation and correlation with spatial thinking and math skills development: https://www.oecd.org/officialdocuments/publicdisplaydocumentpdf/?cote=EDU/WKP(2017)10&docLanguage=En
Thank you for help :-)