A board of directors has the responsibility for setting the strategic direction of the organization. Many times, this is documented in a three or five year strategic plan and the plan has annual goals.
The exercise of creating the strategic plan should not be the end of the strategy discussion. This plan does not exist in isolation; it should be used as the basis for all of the activities taken on by the organization.
My recommendation is that each board meeting should move the organization closer to achieving the goals set out in the strategic plan. The agenda items should only include items that advance the organization towards their goals.
The agenda should show how each item ties into the annual goals. This tactic will make it easier to eliminate agenda items that do not tie into the organizations goals.