Dumb student can also perform good in maths by proper training

It seems that sheer intelligence is not enough to become a young math whiz. It also takes a good attention span and training your mind to "self regulate" or focus on the task at hand.

Its long been believed that persons intelligence or IQ is proportional to maths problem solving skill.

But new research published in the journal Child Development says that a thought process called "executive functioning," which governs the ability to reason and mentally focus, also plays a critical role in learning, especially when it comes to math skills.

"It's often thought that kids don't do well because they're dumb, and there's nothing we can do about it," says lead study author Clancy Blair, associate professor of human development and family studies at Pennsylvania State University. "But not only is executive function pivotal for academic success, it's amenable to training, and this training might make a big difference in a child's ability."
According to Blair's study, by proper teaching skills, we can improve child's academic performance. "Preschool curricula that focus on development of skills to focus on task in hand and self-regulation are needed in a big way," Blair says.

This emphasize on basic primary education that we get in our early school days. Good training in early days can make an average student brilliant in maths.