Arrange for a special school day commemorating the year the school first was established by asking the students to come dressed as was expected of the generation that went to the school at that time. Teachers will teach topics in the style of the period, and student can prepare a play on how a typical school day might have looked like. Find recess games played at the time and teach them to the students. Decorate the halls with photographs or drawings of the school throughout history, and find ornaments that would have been common the year the school was founded. Ornaments can include old maps, pictures of the president in office at the time and old-fashioned science equipment. If possible, recreate an old-fashioned classroom with some desks, chairs and a blackboard.
Ask students in all grades to research the school's history by looking at significant events and finding local or national celebrities who attended the school. Significant events include wars, refurbishments, changes of headmasters or natural disasters. Celebrities might come from sports, politics or entertainment. Classes can take on various projects, including looking at the school's former students who fell in various wars or collecting photographs or drawing of the changing look of the school throughout the decades. Have exhibitions and plays about the history of the school, and invite several generations of alumni to come for a visit and mingle with the current students.
Encourage the students to bring a grandparent to school for the day. If students do not have any grandparents living close by, encourage them to bring an elderly neighbor, friend of the family or other relative. Instruct the cafeteria staff to prepare double rations that day, and arrange for activities to highlight the bond between the generations. Activities can include making a family tree, doing arts and crafts projects together or talking about favorite books, movies or artists. Ask students to introduce their guests to their classmates, and hold a special assembly where you invite some of the older guests to make a speech.
While history is important to define school spirit, students also have to consider future generations and how they will be impacted by the current establishment. Hold a "Future Generations Day" as part of Spirit Week and encourage the students to think about their legacies when preparing for events and activities. Have science classes where the students look at local environmental issues and the prospects they leave to future students. Give out assignments charging students to design the look of the school in the future through models, drawings and paintings. Have an essay contest about a regular school day in 100 years time. Ask the students to make a future Wall of Fame, where they hang their photographs together with their names and hoped-for professions.