Oregon Revised Statutes Revenue and Taxation § 306.150

(a) By periodically distributing to them bulletins prepared and published by the department pertaining to the principles and practices of assessment, apportionment, levy and collection of public taxes;

(b) By periodically distributing to them lists of selected readings in the fields of assessment and taxation; and

(c) By establishing and conducting such classes of instruction for county assessors and tax collectors in the principles and practices of assessment and collection of public taxes as in the opinion of the Director of the Department of Revenue may be expedient and beneficial to the needs of the state and the advancement of the tax assessing and tax collecting professions.