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1. It is customary to stand when the shirah of Az Yashir is read from the Torah.
2. In the seventh aliyah (as well as in Maftir), the baal korei reads zecher zeicher Amalek (first zecher and then zeicher).
3. It is customary to eat buckwheat(shvartze kashe). When buckwheat is eaten separately (not during a meal), if the kernels are whole, say the berachah of ha’adamah. If the kernels are crushed, say the berachah of shehakol.
4. The Maharal of Prague instituted the minhag of gathering children on Shabbos Shirah and relating to them the story of krias Yam Suf. The children would be told how the birds sang and danced along when the Jews sang Az Yashir, and how the children plucked fruits from the trees growing in the Yam Suf and fed them to the birds. The children would then be given shvartze kashe and told to feed the chickens and birds.
The Rebbe writes that we did not see this minhag being done in the home of the Frierdiker Rebbe. However, this reservation was only with regard to feeding birds on Shabbos, as that may pose a halachic issue. Children should certainly be told about krias Yam Suf (as described above), and should be encouraged to display compassion to animals.