The Explorer: Not up to par

A select number of students also are given the National Assessment of Educational Progress (NAEP) exam.

But a controversy has arisen between the validity of TerraNova and NAEP in which critics point to the chasm that separates results from the two exams.

Last year’s TerraNova scores placed Arizona fourth-graders at 10 percent above national averages in math.

NAEP, however, placed fourth-graders in Arizona at levels well below national averages. For example, 30 percent scored below proficient in math; the national average is 21 percent.

Horne discounts the discrepancy, though. He believes the sheer number of TerraNova exams administered in the state — 600,000 — makes it a better measure than the highly-selective group of 6,000 NAEP exams.

“NAEPs are meaningless because they aren’t given under the same conditions in all states,” Horne said.

Ladner said that NAEP is the better tool because it has consistently shown since the 1970s that Arizona scores have remained flat, and because 29 different versions of NAEP have been given in Arizona since 1992, but the results always come back the same.

“Arizona scores below the national averages in nearly all areas,” Ladner said. “In Arizona 48 percent of the fourth-graders can’t read, according to NAEP.”