I am currently studying petroleum engineering at The University of Houston. Although I was typically a strong student in all areas throughout high school, there were some teaching styles I encountered that complicated the material more than was necessary. In fact, I avoided certain subjects for several years simply because of one unpleasant introductory class.
I believe that most students who struggle with certain academic areas are capable of doing well, but something about the process usually has to change in order to make this happen. Every person is different, and it is important to access what is actually causing the problems for that particular student. The most humorous personal example I have to tell is that I needed a tutor for Algebra I right as I was going into middle school. After that, I went on to take AP level calculus in high school and this semester I am taking the last math course required for engineering majors. I never needed any supplemental instruction after Algebra I.
The problem was not that I was "not a math person" or that Algebra I was the hardest class I ever took. I had developed some bad habits and studying techniques that were proving detrimental, and had not really made a difference until I got to the new level of material. After my tutor and I identified the issues and worked to fix them, every math class became much easier.
I think most students who are struggling with concepts or think they are "bad" at a particular subject are just in a situation like I was once. With a personalized approach and the right attitude, the difficulty can be overcome.
University of Houston - Current Undergrad, Petroleum Engineering
ACT Composite: 34
ACT English: 32
ACT Math: 35
ACT Reading: 36
ACT Science: 31
SAT Composite: 2330
SAT Math: 770
SAT Verbal: 800
SAT Writing: 760