And from the day on which you bring the omer offering the day after the sabbath you shall count off seven weeks. They must be complete: you must count until the day after the seventh week fifty days; then you shall bring an offering of new grain to the Lord. -Leviticus 23:15-16
As principal of a Jewish school in the US, I always felt that once we hit Tu Beshvat, the year is over there is no time or energy left to do anything except cope with the succession of holidays, get ready for the end of the year, and work on the plans, hiring, etc. for next year. Any kind of continuity, of concentration, of orderly instruction is pretty much shattered by one special day after another, with their associated preparations. And if that is true in the microcosm of the Jewish school in the Diaspora, imagine what goes on in the Jewish state!
Purim, for example, eats up a full week first there's getting ready, and then the school party has to be two days before Purim, for there is no school on Purim, and the day before Purim is the Fast of Esther, when it's considered inappropriate to party; and then the day after is Shushan Purim, another day off. Similarly, Pesach vacation starts a week before Pesach, which means that school sedarim and other festivities have to be held before the dismissal, cutting into the little time after Purim that was not already devoted to preparing for Pesach. For Pesach (and the weeks before) especially, not only schools, but the whole country goes into a kind of shutdown mode normal obligations are set aside for cleaning, shopping, and travel. Whatever prophet said "dust is not chametz" has no following in the holy land; for example, the county street-sweeper makes its annual visit to our parking lot the week before Pesach
But that's only the warm-up. Traditionally, the period from the second day of Pesach until Shavuot, the "counting of the Omer," was treated as a period of mourning. No one knows why the Talmud refers to a plague that killed thousands during the Roman period some see in that a cryptic reference to events of the disastrous Bar Kochba revolt. Others suggest that the period during which the wheat is ripening is fraught with danger one poorly timed hailstorm can destroy a year's food supply; hence, we superstitiously avoid acting too happy until the harvest is in. If anything, the seven weeks of counting should be a calm and productive time. But whether by plan or by coincidence, we've inserted modern historical commemorations into this period, leaving no week untouched. The week after Pesach there's Yom Hashoah; the week after that there's Yom Hazikaron and Yom Ha'atzma'ut and since the latter comes this year on a Wednesday, and many people are off on Fridays anyway, that Thursday will be taken as a vacation day by thousands. Then a normal week, followed by the week in which Lag B'omer falls. Not really a holiday, with unknown origins, this 33rd day of the counting of the Omer, on which traditionally the mourning customs of the period are temporarily lifted, is thus a day of many weddings, and has become a kind of children's fire festival bonfires, often huge, are de rigueur that night and woe to any construction site without a security guard. A year's worth of carbon credits up in smoke. The following week is Jerusalem Day and the week after that Shavuot. By then of course we're approaching June, so schools are heavily into exams, rehearsals for graduation performances, etc.
There's something wonderful about this intense rush of religious and historical symbols, a period in which the various dimensions of Jewish identity saturate the public space and consciousness - with symbols and songs and tastes and smells. Unless, of course, you're trying to get something done.