I think that this is the part of the Mishna that is most relevant to college:
רַבִּי מֵאִיר אוֹמֵר: לְעוֹלָם יְלַמֵּד אָדָם אֶת בְּנוֹ אוּמָּנוּת נְקִיָּה וְקַלָּה, וְיִתְפַּלֵּל לְמִי שֶׁהָעוֹשֶׁר וְהַנְּכָסִים שֶׁלּוֹ. שֶׁאֵין אוּמָּנוּת שֶׁאֵין בָּהּ עֲנִיּוּת וַעֲשִׁירוּת, שֶׁלֹּא עֲנִיּוּת מִן הָאוּמָּנוּת, וְלֹא עֲשִׁירוּת מִן הָאוּמָּנוּת, אֶלָּא הַכֹּל לְפִי זְכוּתוֹ.
Rav Meir is saying not focus on a specific method of earning your livelihood. Rather we should focus on what we are physically doing with our time. (…נְקִיָּה וְקַלָּה וְיִתְפַּלֵּל….)
According to most interpretations of the Mitzvah of Limud Hatorah, a person is not obligated to work less so that he can learn more. The obligation of a working individual is to keep the Torah on his mind even while he works. Whereas one who is idle, is obligated to study with all his diligence.