Tu B'Shevat Shiur. We are going to have a sort of peros tish today - when all the different Chasidus sit by a big table and they have tons of fruit. Usually 15 kinds of fruit. The Rebbe makes blessings over the fruit, they sing the 15 Shir Ha Ma'alot (The Song of Ascents). Psalms 120-135. They signify a rising up. King Solomon had 15 steps that led up to his throne and they would sing on each step a different song of ascent when they went to speak to the King.