Josh
(Josh Cohen)
1
This thread is for compiling the different systems of mental math as well as books and training tools.
I’ll link to pages about some of the methods I’ve heard of:
https://www.vedicmaths.org/introduction/tutorial/tutorial.asp
Practice sites:
http://windhoff.net/mental_arithmetic/#Multiplication
Post links if you know of any good information on the subject. 
1 Like
geezer
2
Here is a good practice site:
http://www.momonix.com/calc/