California ranks fifth-lowest in the nation in students' vocabulary -- a critical part of reading, according to results of national standardized tests released Thursday.

Overall, California fourth-graders in 2011 scored below all states except in Alaska, , Louisiana, New Mexico and the District of Columbia. But Asian, African-American and Latino fourth-grade scores improved, compared with 2009, the only other time that vocabulary was tested and scored separately from reading.

California eighth-graders also scored fifth from the bottom, just above Hawaii, Mississippi, Louisiana and the District of Columbia.

"What you're seeing is a lack of vision in educational leadership across the board in California," said Arun Ramanathan, executive director of the Oakland-based advocacy group Education Trust-West. "Students are not getting access in early grades to high-quality reading instruction."

The National Assessment of Educational Progress, also known as the Nation's Report Card, is administered to representative samples of students in grades four, eight and 12. The newest scores are from tests given in 2009 and 2011.

Nationally, scores barely budged overall. The average national score in 2011 was 263 for eighth-graders and 217 for fourth-graders; in both grades, California students' average was 9 points lower.

Twelfth-graders were tested only in 2009 and only in 11 states that volunteered; California was not one of them.

With few exceptions, California scored poorly when broken down by demographic characteristics such as gender, ethnicity and poverty. For example, in 2011 the state's Latino fourth-graders scored 7 points below Latinos nationwide, and the state's Asian eighth-graders scored 2 points below Asians nationwide.

With the scale running from 1 to 500, does that indicate a national vocabulary crisis?

"There's not any more of a crisis than we see in reading," said Margaret McKeown, a professor at the University of Pittsburgh School of Education, in an NAEP conference call Wednesday. But, officials concede, many U.S. students score below grade level in reading.

NAEP did not assign rankings to the score, making it difficult to extract meaning from them. States can compare scores with each other and their change over two years, but can't judge whether their students are proficient or not.

But test officials said the words tested -- about 15 for each grade level -- include those that students should reasonably be expected to understand at their grade levels.

"There are no trick questions," said Jack Buckley, a commissioner with the National Center for Education Statistics.

Nationwide on the 2011 tests, three-quarters of the eighth-graders tested understood "anecdotes," "edible," "enticing" and "replicate," for example, but fewer than half understood "urbane."

Vocabulary mastery is critical to reading, officials said. "Kindergartners' vocabulary predicts reading comprehension later in elementary school," McKeown said.

California clearly has farther to go than do other states. Ramanathan pointed out that the state is doing worse even than states spending less on education. And while some of California's 1,000 school districts are advancing in teaching English, he said, the improvements are piecemeal rather than state-led as they are in states like New York, Kentucky and Washington.

NAEP seeks to assess students' knowledge of words in context, rather than asking them to choose definitions. Words tested generally are those found in written, not spoken, language and are examples of the kind of words that students need to be successful in reading and writing. The national tests have been conducted since 1969 in reading, math, science, writing, U.S. history, civics, geography and other subjects.

Contact Sharon Noguchi at 408-271-3775. Follow her at Twitter.com/NoguchiOnK12.