How Will My Grades Effect My Chances?

<p>Hello! I am a junior in high school, and we are nearing the end of our 1st semester. Throughout my high school career, I have maintained a 3.7+ GPA. This year; however, has been quite difficult for me. I have no idea why but this 1st semester has been a struggle for me. Reasons ranging from excused absences to stress to personal issues. Currently, my schedule consists of honors/AP classes and other notoriously difficult classes in my school. As of right now, I have 2 A's and the rest are B's/B-'s. For me this is unacceptable and I plan on working my rear off to get all A's next semester. I am involved in several in-school extracurriculars as well as a few outside of school. I'm also planning on volunteering at the local hospital soon. My dream schools are University of Notre Dame, University of Pennsylvania & Duke University (in that order.) I was just wondering if this drop in my grades will severely impact my chances of going to any of those schools? Thank you all so much in advance and Happy Thanksgiving! :)</p>