In 2014, the U.S. Bureau of Labor Statistics reported an annual median salary of $38,370 for medical and clinical laboratory technicians. The BLS also predicted 30% employment growth for these technicians from 2012-2022, which is much faster than average.
Study math. Software engineers sometimes create the mathematical algorithms that allow software to function. Focus on developing and maintaining your math skills in order to do your best once you've obtained a position as a software engineer.
I'm not sure as to what type of classes, one should take but I can tell you what computing skills an engineer should have, especially if your interest lies in mechanical systems! Programming/Coding. An engineer should have at the very least, a basic understanding of the principles related to competent programming and computer science.