Finds that the first-ever state survey of student readiness for kindergarten in Washington state in 2004 revealed a significant gap in children's readiness for school. Teachers reported that only forty-four percent of incoming kindergarten students were adequately prepared. Student preparedness tended to be much lower in classes with high rates of poverty.

Declares that, as the legislature adopts policies and increases investments to support early learning, it is critical to be able to measure over time whether kindergarten readiness increases in response to these efforts. The legislature needs to be accurately apprised of whether children are ready to succeed in school when they first enter kindergarten.

Requires the office of the superintendent of public instruction to: (1) Conduct an inventory of the kindergarten readiness assessments used by school districts with incoming kindergarten students;

(2) Conduct an inventory of kindergarten readiness assessments used in other states or recommended by research; and

(3) Recommend to the legislature, for statewide adoption, a single culturally appropriate and inclusive kindergarten readiness assessment and a method for statewide data collection that will allow for data analysis and measurement of trends over time in kindergarten readiness. The assessment must measure prereading and premathematics skills.

Directs the office to report its findings and recommendations to the education committees of the legislature by December 1, 2006.