According to an annual self-assessment released recently, the town’s public schools are making progress in increasing the achievement of all students. The assessment looks at measures such as report card grades, MCAS scores, English proficiency, and the number of Advanced Placement courses taken and completed by high school students, college graduation, and the difference in results between ethnic groups. In overall achievement, the schools rated an A-minus, with its lowest grade, D, in the gap in improvements in MCAS scores between higher- and lower-income households. - Andreae Downs