Measuring student growth using student learning objectives

From: http://ies.ed.gov/ncee/edlabs/projects/project.asp?ProjectID=369
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Student learning objectives (SLOs)—classroom-specific growth targets chosen by individual teachers and approved by principals—are becoming popular as alternative measures of student growth because they can be used to evaluate teachers in any grade or subject.  Although very little of the literature on SLOs addresses their statistical properties, key findings show that:

• SLOs have the potential to better distinguish teachers based on performance than traditional evaluation metrics do, but no studies have looked at SLO reliability.  Most of the limited evidence on the statistical properties of SLOs is on the proportion of teachers achieving SLO objectives. Whether that differentiation represents true differences in teacher performance or random statistical noise is unknown.
• Little is known about whether SLOs can yield ratings that correlate with other measures of teacher performance. Only three studies have explored the relationship between SLO ratings and standardized assessment-based (value-a dded) growth measures. These studies found small but positive correlations. More research is needed as states and districts roll out SLOs as teacher evaluation measures and instructional planning tools.
• Until some of the research gaps are filled, districts that intend to use SLOs may want to roll them out for instructional planning before using them in high-stakes teacher evaluations. Several studies found teacher concerns about fairness in SLO implementation. This is no surprise, because SLOs are difficult to make valid and reliable. They are by definition customized to individual teachers and based on the professional judgments of teachers and principals. Making SLOs an important component of high-stakes evaluation could undermine their validity, because it means that teachers are in essence grading themselves.
• Studies of teacher experiences with SLOs indicate that SLOs can require substantial training and technology infrastructure and that they can be time-consuming for teachers and evaluators alike.