There is a major dispute regarding this matter. Maimonides (in his Commentary on the Mishnah) explains that the meaning of Shtarei Hedyotot refers to any study of wisdom that does not contain the wisdom of the Torah. However, the Ramban and the Rashba permitted it. The ruling of Maran the Mishna Berurah (Siman 307, 65) is that the custom is to be lenient, though one who is “God-fearing” (Yere Shamayim) should be stringent. Therefore, generally speaking, any study of wisdom, grammar, arithmetic, or general worldly knowledge that makes a person wiser falls under this definition of “secular wisdoms” (Chochmot Chol).

In a case where an exam is scheduled for the coming week and a person fears that if they do not study on Shabbat they will fail, it is permitted for two reasons: due to the lenient view regarding the study of secular wisdoms on Shabbat, and because if they do not study, they will be distressed on Shabbat. Therefore, in a time of need, we permit studying on Shabbat initially if it is necessary. We add that this does not constitute “preparation” from the holy (Shabbat) for the secular (weekday), as the learning and knowledge are acquired during Shabbat itself. However, one must be careful not to say, “I am going to study now for the exam I have this week.”