Does growth model measure up to Indiana law?

There’s a lot to be said for the Indiana Growth Model, the statistical method that Indiana uses to calculate year-to-year student growth on math and English test scores. It’s far from perfect, but it’s a much better measure of how schools are doing than looking at how many students pass the tests.

It may be a challenge, though, to use the model while complying with a state law that says Indiana must measure students’ growth in relation to their proficiency on state standards.

That’s especially true now that Indiana has adopted new “college and career ready” standards and will be giving a new version of the ISTEP+ exams, aligned with the new standards, in the spring of 2015. Is it possible to measure growth in proficiency when you give a test for the first time?

The law in question is House Enrolled Act 1427, adopted in 2013. It says accountability measures “must be based on measurement of individual student academic performance and growth to proficiency” and “may not be based on a measurement of student performance or growth compared with peers.”

But the State Board of Education voted this month to use the growth model in 2015. Indiana’s Center for Education and Career Innovation and the state Department of Education recommended the approval.

CECI and DOE staff cited an analysis by testing expert Damian Betebenner, who helped design the Indiana Growth Model and advises the state. He suggests using a statistical adjustment called “equi-percentile concordance” to correlate the 2014 test with the new, 2015 test. That, he says, will make it possible to keep using the growth model to measure students’ test-score gains.

But his report to the board also says that, with the move to new ISTEP+ exams, it won’t be possible to evaluate students’ gains or losses on a single test from one year to the next. “Without gains/losses,” he writes, “growth must be calculated using norm-based metrics that compare like students as they progress from the ISTEP+ to the Career and College Ready Assessment.” (Italics added). Continue reading

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Indiana public schools ‘out-grow’ charter, private schools

School-choice advocates argue that children will get a better education if they can leave public schools for charter or private schools, especially in urban areas. The Indiana Growth Model tells a different story.

It suggests public schools, overall, are performing better than charter schools or the private schools — most of them religious schools — that are getting state vouchers.

The growth model is a statistical tool that measures students’ test-score gains compared to those of students with similar academic histories. It may not be perfect, and critics argue that it shouldn’t be over-used. But it’s unquestionably a better measure of school effectiveness than standardized test scores or school grades, which have been shown to correlate closely to student demographics.

You can download 2012-13 growth scores for all the schools in the state from the Indiana Department of Education website. Sort and rank them, and what do they show? Continue reading

Indiana growth scores for schools yield surprising results

Which Indiana school districts are the most effective at improving student achievement? Let’s hear it for Eastern Greene School District, a rural, high-poverty district in southern Indiana? And Southwest Dubois School Corp., another small, rural district.

How about the best big school district? Brownsburg Community Schools takes the prize. Some typically high-achieving schools — Carmel, Zionsville and Hamilton Southeastern — are also among the elite. But so are districts that aren’t thought of as high fliers, such as Elkhart, New Albany and Lawrence Township in Indianapolis.

Here’s another surprise. A few charter schools do great at promoting growth, but the overall record for charters is pretty mediocre. The same is true for private schools.

This is according to school ratings on the Indiana Growth Model, a statistical tool that assesses students’ annual improvement in test scores compared to that of others with similar academic histories. The model assigns a growth percentile score to each student.

Indiana has compiled median growth scores for schools and districts for years, but it has never made a big deal out of them. Yet the growth model is arguably a much better measure of school effectiveness than A-to-F school grades Continue reading