National Israeli holidays / Chagim are generally all Jewish Holidays, plus the addition of Independece day. Following is a list of all Jewish Holidays, and Vacation days in Israel.
Rosh Hashana - 23-24/09/2006
The beginning of the Jewish year, which is one of the three most sacred holidays in the Jewish religion. Rosh hashana lasts for two days on Tishrey first and second. School students usually have 3 to 4 free days, starting one day before the official Jewish holiday.
Yom Hakkipurim - 2/10/2006
The day of amendment is the holiest day of the year, during which all Jewish people must fast for an entire day (25 hors). It occurs 10 days after Rosh Hashana on Tishrey 10. School kids have two days off, starting one day before the ooficial Jewish holiday.
Sukkot and simchat Torah - 7/10/2006- 14/10/2006
Sukkot is a very special holiday in which many Israelis set up special tents called "sukka" in their back yard, and invite all their friends and family to visit. Sukkot starts on Tishrey 25 and ends on Tishrey 31st, which are eactly 7 days. It is foillowed by "Simchat torah" in which we celebrate the first chapter of the torah, which will then be read throughout the entire year.
School kids have 10 days off, starting one day before the holiday.
Hanuka - 1612/2006-2312/2006
The holiday when we all light our Hannuka lamps and eat doughnuts for 8 days to celebrate the victory of the Maccabim over the occupying Greek. Starts on Kislev 25 and ends on Tevet 2. School kids have time off for 9 days starting one day before the holiday starts.
Tu Bishvat - 3/2/2007
Not a workplace or school vacation, but my personal favorite - is the holiday when we celebrate the beginning of the year for all plants and trees. It is custom to plant trees and new flowers on Tu bishvat (Shvat 16th), and if you ask around you may even join a new forest planting organized by the JNF.
Taanit Esther and Purim - 13/3/2006-15/3/2006
Purim is a holiday when we all wear costumes. It is the happiest holiday in Israel, and a very intersting time to visit. It is not a school vacation though..
Passover - 13/4/2006-19/4/2006
The longest holiday is when we celebrate the freedom the Jewish people have been granted from the Egyptian people. The peak of the holiday is "Leil Haseder" when we all sit down for big family dinners and tell the tale of the "Haggada".
In the Kibbutzim, passover is the holiday of the harvest, when all Kibbutzim have the passover harvest festival.
School kids get a three week vacation from school, startng a few days before the holiday starts.
Memorial Day and Independence day - 2-3/5/06
The two following days are when we remember all those we lost for the country, and celebrate our independence. School is off from the middle of memorial day till the end of independence day (2 days).
During memorial day there are many ceremonies around the country which Israeli attend and watch on TV.
During Independence day we all celebrate in big parties, and out in the streets.
Lag Baomer - 16/5/2006
33 Days after passover is the Jewish holiday of the harvest season, in which Jewish people set up big bonfires around the country. It is a one day holiday for school kids.
Shavuot - 2/6/2006
The third holiest holiday, when families meet for a typical dairy lunch or dinner. School kids have 2 days off, starting one day before the holiday.
Summer break - 20/6-30/9
There are no Jewish holidays during summer moths, but school is off for a two month period. High school kids start their time off on June 20th, while the rest have to wait till July 1st.