ARITHMETIC OF INFINITY

• Numerical Infinity and the Infinity Computer: this is the official page listing ongoing research based on the Arithmetic of Infinity, as well as the academic prizes and acknowledgments received by Yaroslav Sergeyev.

MATHEMATICS EDUCATION IN THE UK

• Association of Mathematics Teachers Official Website 
• The Scottish Mathematical Council
• N-Rich 

MATHEMATICS EDUCATION IN ITALY

• UMI: the website of Unione Matematica Italiana, based in the Department of Mathematics, University of Bologna (English version available)
• ​RSDDM: the official page of a research group based at the University of Bologna and devoted to mathematics education and the popularisation of mathematics (in Italian)