Blog | Kурсове по английски, БЕЛ, математика и ментална аритметика
Mental arithmetic and its relation to pedagogy

Every educator knows how important it is for the students to be concentrated in class, to have excellent logic while...

See more
What is an abacus? The history of abacus calculating device.

The first significant achievement in the field of arithmetic was made in China, where the local people invented the a...

See more