Yes, the ranking of activities is incredibly important.
I learned this the hard way by viewing my Harvard Admissions file, and seeing just how lucky I had gotten.
In the box at the very top of the “Activities Section” of the Common App, you are told to
“Please list your activities in the order of their importance to you.”
Many people miss this, or don’t properly rank their activities.
Screenshot of the Activities Section of the Common App (Source: Common App)
However, it is essential that you spend time critically thinking about which activities are most important, and ranking them in the order you want the admissions officers to read them.
That’s because some schools will automatically filter out the last 5 activities listed (as these tend to be much less informative/substantial for most applicants).
I didn’t know this when I applied to Harvard, and I got very lucky that the right activities happened to make it onto my admissions summary sheet by chance.
A screenshot of my Harvard summary sheet is above (personally identifying information has been removed). Harvard automatically generates a one-page summary sheet for every applicant so that files can be quickly and fairly reviewed, and I was able to access this information through a Student Records Request.
Note that only 5 activity spots are occupied on the sheet, despite my putting 10 activities down on my Common App.
The 5 activities that made it onto my summary sheet were simply the first 5 activities I listed in my Activities Section. This isn't true for every application (I've seen applications with more and less than 5 activities copied over), but it is something to be aware of since this might be a factor out of your control.
Additionally, note that only the Activity Type (e.g. “Theater/Drama” or “Debate” or “Science/Math”) and Position/Leadership Description (e.g. “Debate Team Captain” or “Intern at Company X”) were copied over onto my summary sheet.
Thus, it is extremely important that you make your 50-character Position/Leadership Description as informative as possible, since this is all the information that the admissions office will see (at least if you’re applying to Harvard).