1) Ch. 1, v. 2: "L'mish'p'chosom" To their families We find no tally of members of each family, only the tribe total. Indeed, Rashi clearly states that knowing the families is only a medium to arrive at the tribal totals. How so?
2) Ch. 1, v. 4: "Ish rosh l'veis avosov" A man who is head to the household of his ancestors What information does this add to the previous words "ish ish lama'teh?"
3) Ch. 1, v. 17: "Va'yikach Moshe v'Aharon eis ho'anoshim ho'ei'leh asher nikvu b'sheimos" And Moshe and Aharon took these people who were designated by names Rashi d.h. "asher nikvu" says "lo kan, b'sheimos," to him here, by names. What is Rashi clarifying with these words?
4) Ch. 2, v. 3: "Keidmoh mizrochoh" Eastward We translate these two words as being synonymous, both meaning eastward. What explanation allows for these two words to mean two separate things?
5) Ch. 3, v. 39: "Shna'yim v'esrim o'lef" Twenty-two thousand Rashi (gemara B'choros 5a) asks that when we add the totals of the Levite families we have 22,300, not 22,000. He answers that since the Torah discusses the Levites being a redemption for the first-born, we must say that there were 300 Levite first-born as well, and their ability to redeem a first-born is used up by redeeming themselves.
This seems to not be very conclusive. Why not say that they cannot self-redeem, and that there were only 150 Levite first-born who were redeemed by another 150 regular Levites, and this is how we account for the missing 300 Levites? For the answers click here!