Hi, I´ll graduate with presumably very good grades from a target school (St. Gallen) next summer and I´m interested in starting a career in consulting afterwards. However, I was quite lazy in High School and only achivied under-average grades. Will this be a problem at the paper screen? All other aspects should fit (1 year voluntary service in 3rd world country, semester abroad, leadership position at a student organizaton).
Importance of High School grades
I guess the answer is: It depends.
I have once heard that McKinsey has this rule that the sum of Abitur, Vordiplom and Diplom (you're German, you understand) should not exceed 5. So in that case, you'd be screwed.
But I believe this is an urban myth. Maybe some of the McK alums here can confirm. I am sure that most firms will ignore bad highschool grades if everything else checks out nicely. At least all that I have worked for or with.
It would also be stupid not to do so. Because why would you not at least look at a very promising candidate just because some grade from half a decade ago were mediocre.
But you can expect some questions on that during your interview, particulalry if your grades were poor in Maths or Physics. I had a question during the final partner interview (the partner in question was ex-McKinsey): "Im Grundkurs in Mathe nur 12 Punkte? Was ist denn da schief gegangen?"
I guess the question was more intended to throw me off balance and see whether I shared his sense of humor, but as a kid in your early twenties, when your job is on the line, a question like that might suffice...
Yep, may be an issue unfortunately. I have heard that for example McK takes a close look at high school grades, especially math.
However, beyond thinking about how prominently (or not) you put it into the application, there is not much you can do about it. So I would not worry about it too much at this point.
It would help to make contact with firms at recruiting events or workshops they organize rather than applying directly for a job.
Finally, once you're invited to interviews, I doubt it will matter anymore. If someone asks, the "I was a bit lazy in school and it somehow worked"-story should be sufficient. You can actually use it to demonstrate "personal development" or "acting on feedback" in the personal fit part ;)
All the best for your applications!