My Writing During Freshmen Year

I came into English 15 without really writing a (real) paper since first semester of my senior year (senioritis kicked in around december and all hope was lost). I took AP Language and AP Literature for my last two english classes in high school. So basically, my writing was about books we read or had to be written in a specific model. Coming into English 15 where you made your own thesis/your own style was much different and little uncomfortable to me. I thought it was hard to come up with something on my own and really make it my own; to make it believable to the audience I was focusing on.
Also I think that one of my biggest struggles was that in my papers in this class I was either being too informal or too formal; I couldn't find the balance between the two. I also think that my papers started off strong, introductions have always been my strongest point (I like to be creative), but then I think that it would start to lose it's purpose towards the end. I need to start strong and end strong. The reason I think that my papers started to lose their purpose or credibility was a little because I was being too wordy. Unfortunately, I didn't realize this until the last paper, when we did an adjective/verb activity in class. I seem to put my words in the past tense a lot/ use extra words that I don't need. Wordiness definitely does not add to the success of a paper.
I am not an english major, but I will be using writing my whole life. I plan to be an elementary school teacher and how would it look if I emailed parents with bad grammar or wordiness? Not so great I would think! Also my major includes pre-k to 4th grade children. If I am teaching at the higher levels I will be teaching them english and I need to know how to write. Also along with my major, I plan on minoring in Spanish. Someday I may have a spanish-speaking child in my classroom and will have to teach him the basics of English. If I don't know how to write well or know verbs or grammar I will be of no help to him! English is definitely something I need to carry with me in my future.