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Tim Myers: The (API) numbers game

Myers' Musings

Posted: May 30, 2009 7:14 p.m.
Updated: May 31, 2009 4:55 a.m.
Let me say at the outset to all the teachers and staff at Helmers Elementary School in the Saugus Union School District: “I love you all!”

Our three youngest children attended Helmers, and they seem well prepared for their subsequent academic challenges. Helmers always bragged about its API rankings and test scores with Blue Ribbon and distinguished-school emblems prominent on the school façade.

However, I always wondered about the performance. I know from study that demographics — particularly the educational achievement of a child’s mother (Father’s achievement is not a reliable indicator) — drive the absolute level of standardized test scores more than the most cunning plans of teachers and administrators.

Thus, with a school community made up of 60 percent of moms with bachelor’s degrees, could trained Rhesus monkeys playing instructional videotapes achieve basically the same result?

Fortunately or unfortunately, the state of California now provides data to calculate just this factor in its Academic Performance Index (“API”) material.

The Department of Education provides two key data points for each school: Its absolute API percentile and its percentile when compared to schools of similar demographics.

The Department of Education assigns each school to a decile based on its API scores compared with the rest of the state.

Being in the top 10 percent gets a score of 10, while being right in the middle earns a 5. One gets the idea.

The official press release from all the school districts in the SCV trumpet the fact (demonstrably true) that the lion’s share of schools in the SCV stand at 8 or above, even at the high school level.

But we need to examine a more subtle number also provided by the Department of Education; the API decile when comparing each school to the population of schools of similar demographics. In this case, one sees how well the schools perform against their peer group.

Now I believe the positive or negative spread between these two numbers reveals the effectiveness of a particular school. Assuming (I think rightly) the demographic group controls for the demo effect, a peer group score higher than the absolute API reveals extra effort on the part of teachers and staff to move their demographic group higher than others similarly situated.

A lower peer group score indicates weakness against the peer group, generating a negative number I call the “sandbag index.”

What does this calculation reveal about Helmers? Not good!

With an API ranking of 9, Helmers ranks only 3 within its peer group, generating a sandbag index of -6.

The Saugus Union School District in total performs equally dismally with an average sandbag index of -4.27.

Tesoro Del Valle Elementary, the newest school in the district, captures the status of worst offender in the SCV with a sandbag index of -7.

What about the Newhall School District? Half of the Newhall schools actually enjoy positive indexes, with their peer API higher than their absolute.

In a matter of some irony, when excluding the three elementary schools west of Interstate 5, the Newhall district actually notches up a positive index of .57.

(Inclusion of the West Ranch schools of Pico Canyon, Oak View and Stevenson Ranch drives down the index nearly 100 basis points to -.4.)

What about the Hart district? It posted a total index of -1.07, but only because of the outstanding performance of Opportunities for Learning, an alternative school, which notched an astounding +7 on the index, scoring a 2 in the absolute but a 9 in its peer group.

The worst performing comprehensive high school in my new index is West Ranch with a -3. (The folks on the West Side need some humility because their high absolute scores ain’t so high when compared to their actual peer groups.)

The best comprehensive high school is Canyon High School with an index of 0, matching a peer group ranking of 8 with an absolute 8.

What does this mean, if anything? Make no mistake, no one would take this information and actually make a first choice to place his or her children in Opportunity for Learning, since the school still possesses dismal absolute scores, but I feel better knowing the Hart alternative schools do nearly the absolute best they can with students in a difficult situation.

On the other hand, those with high absolute scores should retain humility, since within their peer groups they just aren’t that hot.

Tim Myers is a Valencia resident. His column reflects his own views and not necessarily those of The Signal.


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