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Measuring the performance of ultra stable frequency standards such as the Superconducting Cavity Maser Oscillator (SCMO) will necessitate improvement of some test instrumentation. The frequency stability test equipment used at JPL includes a 1 Hz Offset Generator to generate a beat frequency between a pair of 100 MHz signals that are being compared. The noise floor of the measurement system using the current Offset Generator (1.7 X 10(exp -14) at 1 second tau and 6.2 X 10(exp -17) at 1000 seconds), is adequate to characterize stability of hydrogen masers, but will not be for the SCMO. A new Offset Generator with improved stability has been designed and tested at JPL. With this Offset Generator, and a new Zero Crossing Detector recently developed at JPL, the measurement floor has been reduced by a factor of 5.5 at 1 second tau, 3.0 at 1000 seconds, and 9.4 at 10000 seconds, compared against the previous design. In addition to the new circuit designs of the Offset Generator and Zero Crossing Detector, tighter control of the measurement equipment environment has been required to achieve this improvement. The design of the new Offset Generator will be described, along with details of the environment control methods used.

This brief summarizes the findings of a recent book, "Standards Deviation: How Schools Misunderstand Education Policy" (Spillane, 2004), that examines state and local government relations as the standards move from the statehouse to the district policymakers and teachers who attempt to make sense of them. It takes a case study approach, focusing on a single state, Michigan, and strategically sampled school districts. The study is based on empirical data from a four-year examination of approaches to the use of standards in nine Michigan districts between 1992 and 1996. This overview of the study's findings first frames the subject of standards-based reform, and then moves to a discussion of the Michigan math and science standards. Variation in the progress of standards among districts is explored next, followed by a cognitive explanation for the variation and a discussion of districts' resources. Next, variation in teachers' beliefs about and implementation of the standards is analyzed. The overview closes with implications of the study for policy outcomes, analysis, and design.

This brief summarizes the findings of a recent book, "Standards Deviation: How Schools Misunderstand Education Policy" (Spillane, 2004), that examines state and local government relations as the standards move from the statehouse to the district policymakers and teachers who attempt to make sense of them. It takes a case study approach, focusing on a single state, Michigan, and strategically sampled school districts. The study is based on empirical data from a four-year examination of approaches to the use of standards in nine Michigan districts between 1992 and 1996. This overview of the study's findings first frames the subject of standards-based reform, and then moves to a discussion of the Michigan math and science standards. Variation in the progress of standards among districts is explored next, followed by a cognitive explanation for the variation and a discussion of districts' resources. Next, variation in teachers' beliefs about and implementation of the standards is analyzed. The overview closes with implications of the study for policy outcomes, analysis, and design.

Philip Morris Records; memo