Often I heard students complained that math is so difficult and they have lost the interests gradually. New ways need to be adopted in math teaching. It is said that we can make math test online through the math test maker. Do you think it is a good way?

I totally understand your post.  I think It should be helpful, I am preparing some more and will post them soon.
I am highly visual myself and also had a hard time learning math facts. I work teaching basic math to kids with a number of diagnoses.