My grades have stayed nearly the same every semester. My highest semester was .08 higher in GPA than my lowest. A lot of people have one bad class either first or second semester of 1L that drastically changes their GPA. For example, our class rankings were shook up pretty badly by a crim professor that gave a ton of C's 1st semester and a civ pro professor that gave a ton of C's 2nd semester. Most people who got a C didn't get a C in both, leading to a big turnover in who was in the top 1/3, etc.
Overall, you should try to put consistent effort in for both semesters, but realize that grades are to some degree arbitrary- you get a final that matches what you've studied, have people in your class who work harder 2nd semester, or you get a cold during study week. All of these can make a full letter grade difference on a final.
Try to do better, work hard, but don't believe the hype.