Does the Board need to annually approve a Tuition Agreement we have with another school district? Also, do inter-district transfer agreements need to be approved annually by the Board?

State law gives the school board the authority to enter into contracts/agreements for a duration determined by the school board.  If the duration of the agreement is for 1 year, then if must be renewed annually.  If the agreement is for a longer period of time, it need only be reviewed when it expires.  This would apply to both types of agreements you specified.

The statute I referenced is:
332.075 Powers of board.
(1) Any district school board may:
      (a) Fix the days of the year and the hours of the day when schools shall be in session.
      (b) Adopt textbooks and other instructional materials as provided in ORS 337.120 and 337.141 and courses of study for the use of such schools as provided in ORS 336.035.
      (c) Authorize the use of the schools for purposes of training students of an approved teacher education institution, as defined in ORS 342.120, and for such purposes may enter into contracts with the approved teacher education institutions on such terms as may be agreed upon. Such contracts as they relate to student teachers shall have the same effect and be subject to the same regulations as a contract between a licensed teacher and a district school board.
      (d) Develop and operate with other school districts or community college districts secondary career and technical education programs for pupils of more than one district and fix by agreement the duration of the district’s obligation to continue such activity, subject to the availability of funds therefor.
      (e) Authorize the school district to be a member of and pay fees, if any, to any voluntary organization that administers interscholastic activities or that facilitates the scheduling and programming of interscholastic activities.
      (f) Accept money or property donated for the use or benefit of the school district and, consistent with the laws of this state, use such money or property for the purpose for which it was donated.
(2) All contracts of the school district must be approved by the district school board before an order can be drawn for payment. If a contract is made without the authority of the district school board, the individual making such contract shall be personally liable.
(3) Notwithstanding subsection (2) of this section, a district school board may, by resolution or policy, authorize its superintendent or the superintendent’s designee to enter into and approve payment on contracts for products, materials, supplies, capital outlay, equipment and services that are within appropriations made by the district school board pursuant to ORS 294.456. A district school board may not authorize its superintendent or the superintendent’s designee under this subsection to enter into and approve payment on contracts that are collective bargaining agreements or service contracts that include the provision of labor performed by employees of the school district. [Formerly 332.440; 1965 c.100 §140; 1967 c.67 §25; 1967 c.200 §5; 1969 c.311 §1; 1973 c.270 §1; 1975 c.459 §2; 1975 c.770 §21; 1977 c.783 §1; 1987 c.404 §3; 1993 c.45 §41; 1999 c.215 §2; 2001 c.461 §7; 2009 c.94 §5; 2011 c.313 §18]

For more information on this question, Ask OSBA.