It's not just language that benefits from the oral component. Discourse in math is essential too. To make a point, how many times have you asked somebody how they got their answer (right or wrong) and heard, I just knew it. Talking through math problems is very helpful, explaining, reasoning, and problem solving out loud are all basic tools for math achievement. Education Week has a great article about Mathematical Discourse and whether you're a student, teacher or home-schooler, this isn't an article to be missed.
However, if you are a student working alone and don't have the opportunity for discourse, you might just want to keep a math journal with the strategies found here.