Bad Grades Sophmore Year

My freshman GPA was a 3.8 and then sophmore year took a big hit and I ended up with two Cs, three As and one B which is really bad. The two Cs were in one honors class and one math class. However, junior year I’m ending up with a 4.0 both semesters. However, I only took one AP which is AP bio and an honors class for language. My SAT score is a 1520 and I’m confident about getting a 4.0 senior year as well. I’m not the president of a club or captain of a sports team though, but have been involved in activites. I also have work and volunteering experience if that counts. I’m wondering if a good college essay could also increase my chances of getting into a good University. My goal was Vanderbilt University, Georgetown, any of the UCs or University of Pittsburgh, but I doubt I could get into those anymore because of my sophmore year grades. Will I even have a chance of getting into a top university??