Minhagim of Chanukah
- There is no Tachanun at Mincha on Erev Chanukah (eve of Chanukah) and if Erev Chanukah falls out on Shabbat, at Mincha Tzidkatcha isn’t said. 
Fasting on Erev Chanuka
- Many authorities permit fasting on Erev Chanukah.  However, some hold that it’s forbidden to fast on Erev Chanukah.  However, it’s forbidden to decree a public fast on Erev Chanukah. 
- Preferably one shouldn’t fast for a Yeherzeit on Erev Chanukah and if one does one should break one’s fast before the time for lighting Chanukah Candles. 
- A groom who is getting married on Erev Chanukah may fast the day of his wedding. 
Reading Chagai on Erev Chanuka
- Some say that on Erev Chanukah one should learn Chagai chapter 2:10-23 (from “BeEsrim VeArba” until the end of the book). 
Preparing chanuka candles
Learning laws of Chanuka
Having a Festive Meal on Chanuka
- Some say there is a mitzvah to eat a festive meal on Chanukah, while some say that there is only a partial mitzvah in commemoration of the Chanukat HaMizbe’ach of the Mishkan, and some say that there’s no obligation at all.  The minhag is to sing zemirot and say divrei Torah and then certainly the meal is a Seudat Mitzvah. 
Dairy, Sufganiyot, and Latkes
- The minhag is to eat dairy foods on Chanukah, in commemoration of the miracle that happened with the righteous woman Yehudit, who tricked and killed the enemy using dairy. 
- There is a Minhag to eat Sufganiot and Latkes that are fried in oil because the miracle of Chanukah happened with the oil of the menorah. 
Learning on Chanuka
- There is a minhag to give gelt or money to children on Chanuka.
- Many poskim consider this a permissible practice and isn't a violation of following the ways of goyim (Bechukotayhem Lo Telechu). See the footnote for a list of reasons as to the basis of this minhag. 
- Rama 683:1, Nitei Gavriel 1:2-3
- S”A 686:1
- Mishna Brurah 686:1 quotes that Bach and Pri Chadash who forbid fasting on Erev Chanukah. Nonetheless, Mishna Brurah writes that one shouldn’t protest those who have the minhag to fast on Erev Chanukah as a makeup for a fast on Erev Rosh Chodesh Tevet.
- Mishna Brurah 686:1
- Nitei Gavriel 1:8
- Nitei Gavriel 1:9
- Ben Ish Chai (Vayeshev 23), Kaf HaChaim 670:26
- Nitei Gavriel 1:11-13
- Nitei Gavriel 1:15 quoting the Shlah at end of Maasechet Shabbat s.v. Tochechat
- Gemara Shabbat 21b states that the days of Chanukah were instituted as days of “Hallel VeHodaah”. Rashi s.v. VeAsum explains Hodaah as Al Hanisim in birkat hoda’ah of amidah. However, the Rambam (Hilchot Chanukah 3:3) explains Hodah as Simcha. The Yam Shel Shlomo Baba Kamma 7:30 writes that the Rambam holds that meals of Chanukah are a mitzvah and not voluntary (see Moed Katan 9a). The Maaseh Rokeach (Chanuka 3:3) also understands the Rambam this way, as does Rav Shlomo Kluger (Binyan Shlomo on the Rambam Chanuka 3:3). The Bach 670 and 682 ruled likewise. However, both the Tur and S”A 670:1 rule that festive meals on Chanukah are only optional. This is the ruling of Maharam miRutenberg (Teshuva 605), Mordechai Pesachim 49b, Tashbetz Katan 170
Lastly, Rama 670:2 writes that there is a partial mitzvah to have a festive meal on Chanukah as a commemoration of the Chanukat HaMizbe’ach in the desert.
- Why didn’t Chazal institute a festive meal on Chanukah? 1)The Levush 670:2 explains that there is a meal on Purim because the miracle was that Jews lives were saved from a physical threat, whereas on Chanukah the threat was a spiritual one against the Jewish soul. 2) The Taz 670:3 asks on the Levush, isn’t a spiritual threat greater than a physical one?! Therefore, the Taz offers another explanation: since the miracle of Purim was made famous and brought happiness in this world, whereas on Chanukah the famous miracle of the oil only benefited the Jewish people in the next world and so there’s no institution of a festive meal. 3) The Chochmat Shlomo 670:2 says that since the spiritual threat of Chanukah was more dire, the miracle Hashem performed deducted from the merits of the Jewish people. 4) Halichot Shlomo (pg 320 note 32) explains even though we won the war and returned to the Mikdash we continue to fight the culture of the Greeks to this day and so there’s no festive meal.
- Rama 670:2, Maharam miRutenberg (Teshuva 605), Mordechai Pesachim 49b, Yalkut Yosef (Moadim, pg 193), Chazon Ovadia Chanuka pg. 15-16. Kaf HaChaim 670:16 writes that the practical application of this is that since it’s a Seudat Mitzvah a Talmid Chacham is permitted to benefit from it.
- Rama 670:2, Ran Shabbat on Rif 10a (brought in Bet Yosef 675), Maharshal Teshuva 85, Kitzur S”A 139:71, Chayei Adam Chanukah 154:3, Nitei Gavriel (Chanukah 51:12). See Nitei Gavriel who writes that the Sephardim don’t have this minhag. However, Ben Ish Chai (Vayeshev (first year) #23) records this as a Sephardic minhag although he adds in Halacha 24 that the incident of Yehudit happened many years prior to the Chanukah story. Kaf Hachaim 670:17 agrees. see Cheese and Dairy on Chanuka Chabad.org
- Sarid UPalit (pg 8) translates a letter of Rabbi Maimon (father of Rambam) who writes that one shouldn’t be lenient in any Minhag and specifically mentions the Minhag is to make Sufganiot on Chanukah to publicize the miracle of the oil. This minhag is mentioned by the poskim including Yalkut Yosef 671:15, Chazon Ovadia Chanuka pg. 18, and Nitei Gavriel (Chanukah 51:13). Halichot Shlomo (Moadim, vol 1, pg 318) adds that perhaps the minhag is to have Sufganiyot because in Al HaMichya we say Al Mizbechecha remembering the Mizbe’ach which had to be put in genizah because of the Greeks. Nitei Gavriel (Chanukah 51:13) adds that the minhag is to have Latkes. seeHalachos of Sufganiyot by Rabbi Aryeh Lebowitz
- Yalkut Yosef 670:4 writes that it’s good to learn Hilchot Chanukah on Chanukah and quotes Salmat Chaim who agrees. See Alim LeTerufah (Miketz 5769 pg 48) who quotes the Orchot Chaim (a Rishon) that this is an obligation, however, he comments that in the hand written copies of the Orchot Chaim this text is omitted.
- Otzer Minhagei Yishurun (19:4, pg 50) writes that the minhag is for children to play Dreidel because the Greeks who forbade gathering to learn the Talmidei Chachamim used the Driedel as a pretense for gathering to learn Torah. Minhagim VeHalichot Shel Maran Chatam Sofer (14:11, pg 181) writes that the Chatam Sofer kept this minhag. For more sources and reasons see Nitei Gavriel (Chanukah 51:1), Bnei Yisaschar (Kislev 2:25), and Piskei Teshuvot 670:4.
- Rav Tzvi Cohen in Chanuka-Dinim U'Minhagim (2:5, pg. 13) writes that it is forbidden to play for real money unless everybody returns the money. that they gained to its original owner. Piskei Teshuvot (670:4 n. 25) quotes the Shefa Chaim OC 2:283 who says that there is no issue of gambling because just like a father and son may gamble since they don’t care who wins or loses, on Chanukah everyone is like one family. Nevertheless, Nitai Gavriel 51:3 says that one should be strict unless it is with very little money. Rabbi Aryeh Lebowitz (“Playing Dreidel on Chanuka”) warns that one should be especially careful that the money doesn’t get out of hand because it’s a particularly bad idea to gamble under the cover of religious observance.
- Moed LeKol Chai 27:77 offers a kabbalistic reason for giving Talmidei Chachamim and children monetary gifts on Chanuka. chabad.org notes that the chabad minhag is to give gelt to children. Piskei Teshuvot 670:3 records that such was the practice of the steipler. A possible source for giving gifts on Chanuka is the Rambam (Chanuka 3:3) who writes that there's a mitzvah of simcha on Chanuka and regarding Yom Tov the Rambam (Yom Tov 6:18) includes giving gifts in simcha.
- Avnei Yishfeh 1:129 writes that there's no violation of following non-Jewish practices in giving Chanuka gelt since there's a reason for this practice and the prohibition of Bechukotayhem only applies to a nonsensical practice. Mishnat Aharon (p. 117) cites this. A few websites including Torah Acheri HaTzava and kipa.co.il believe that there's no prohibition of following the ways of non-Jews when giving gifts on Chanuka since it isn't religious and has Jewish sources. On the other hand, Rav Hershel Schachter (Chanuka and the Development of the Torah She'Baal Peh (min 39-41)) explains that the old minhag was to give teachers of Torah a little extra money on Chanuka but the modern America practice of giving presents is based on the Christian practice surrounding Santa Claus.
- Rabbi Aryeh Lebowitz in a shiur on yutorah offers 7 reasons for the practice of giving presents on Chanuka:
- There is an aspect of simcha on Chanuka (Rambam Chanuka 3:3) and a way of fulfilling simcha is by giving children what they like (Rambam Hilchot Yom Tov 6:17-18).
- There is an idea to give Tzedaka to poor children on Chanuka (Magen Avraham 670, Chanukat HaBayit (Machon Nachalat Tzvi p. 71), Rivevot Efraim 1:440:3). The Belzer Rebbe extended that to giving money to all children so as not to embarrass the poor (Chayim Sheyesh Bahem Moedei Hashana, by Rabbi Yitzchak Gross, p. 248).
- Emet LeYakov OC 670 suggests that the practice began when the parents gave the children money to give the teachers who taught Torah, so that Torah was supported on Chanuka. In order that the children not feel bad, the parents also gave them a portion of the money to keep.
- Siftei Chayim (Moadim, vol 2. p. 134, Rabbi Friedlander) explains that since the Greeks outlawed learning Torah and children couldn't learn, after the war parents had to bribe them to learn again. As a way of remembering that we give children gelt today. This can also be found in Likutei Levi Yitzchak (Igrot, p. 358).
- Binat Yisrael (Rabbi Yisrael Shapiro, p. 63a) explains that the more we give towards a holiday the more we cherish it.
- Rabbi Flug quotes that after the war the winners would distribute the loot to the soldiers and poor. Giving gelt is a way to commemorate winning the war.
- After the war, Antiochus allowed Israel to mint their own coins, so they would distribute these coins around Chanuka time in order to remember the Chanuka miracle of the war.
- Chabad.org presents another 2 reasons including
- The halacha is that you may not benefit from the Chanuka candles even to look at the image on a coin. To remind ourselves of this halacha we give Chanuka gelt (Likutei Levi Yitzchak, Igrot, p. 358).
- The Greeks believed in materialism as an ends into itself. Our victory over the Greeks showed that we can channel the good in physicality towards spirituality. Hence we give gelt on Chanuka (Likutei Sichot, vol. 10, p. 291).