On a day when American students learned their science scores on an international test were flat, Pennsylvanians got results of a statewide test that showed more than four in 10 students are not proficient in science.

Yesterday was a big science day with the releases of the 2007 math and science results of the Trends in International Mathematics and Science Study -- known as TIMSS -- and the science results of the spring Pennsylvania System of School Assessment, or PSSA.

While Pennsylvania has tested reading, math and writing for many years, these latest PSSA scores are the first statewide science results. The tests were given in grades four, eight and 11.

Overall, 56.2 percent of test-takers were considered on grade level by scoring proficient or advanced. The results showed that 81.5 percent of fourth-graders, 52.7 percent of eight-graders and 35.7 percent of juniors scored on grade level.

"We are sending the large majority of our students to college or into the work force without the tools to compete in our science-rich world," state Education Secretary Gerald Zahorchak said.

He said it's another reason why the state needs new high school graduation requirements.

The state science scores mirrored some of the patterns found on the state math, reading and writing tests, including how juniors often don't score as high as younger students.

In some school districts, more than 95 percent of fourth-graders scored on grade level, including South Fayette, North Allegheny, Upper St. Clair, Hampton, West Jefferson Hills, North Hills and Mt. Lebanon.

But by 11th grade, all of the percentages in those districts were lower, with the highest at 72.2 percent in Upper St. Clair.

The lower scores at higher grades on the state science tests didn't surprise Nancy Bunt, program director for the Math & Science Collaborative, which serves southwestern Pennsylvania and is based at the Allegheny Intermediate Unit.

Dr. Bunt said that children in the lower grades often have a hands-on science program that probes the nature of science, not just the memorization of facts.

By high school, some students are taking courses that emphasize memorizing facts without adequate hands-on understanding, and others don't take upper-level science, she said.

The collaborative's survey of 77 school districts showed that 88 percent of graduating seniors received a C or better in biology while just 41 percent did so in 2007.

Another pattern emerging from the testing is the significant racial achievement gap. Only 29.2 percent of black students scored proficient or advanced overall, including just 8.2 percent of the black 11th-graders.

For the international tests, 425,000 students across 59 countries participated in at least one exam.

On the science portion of TIMSS, U.S. students scored above the international average in both grades four and eight, although many of the top-scoring test-takers were in Asia.

In grade four, the average American science score was measurably lower than in Singapore, Chinese Taipei, Hong Kong and Japan. Six other countries had scores similar to the U.S.

In grade eight, students in nine other countries did measurably better in science: Singapore, Chinese Taipei, Japan, Republic of Korea, England, Hungary, Czech Republic and Slovenia. Three other countries had scores similar to the U.S.

Since 1995, the average science score for American fourth-graders has fallen and the score for American eighth-graders has grown, but neither one significantly.

In the math portion of TIMSS, American students not only exceeded the international average in 2007 but also did better in both grade levels than they did in 1995. Like in science, many of the top-scoring students are in Asia.

On the fourth-grade math test, students in eight places did measurably better than in the U.S.: Hong Kong, Singapore, Chinese Taipei, Japan, Kazakhstan, Russian Federation, England and Latvia. In four others, they did about the same as the U.S.

On the eighth-grade math test, students in Chinese Taipei, Republic of Korea, Singapore, Hong Kong and Japan were measurably ahead. Those in five other places had scores similar to the U.S.

The American math results showed a narrowing of the black-white achievement gap for both grades four and eight.

U.S. Education Secretary Margaret Spellings credited the math improvements to the federal No Child Left Behind Act, which, among other things, requires states to test most grade levels annually in math and reading. That has resulted in many schools spending more time on math and reading.

"Today's TIMSS results reconfirm what we have long known -- if we set high expectations, our children will rise to the challenge," she said.

TIMSS also looked at school culture and found that at both fourth and eighth grades "mathematics and science achievement was highest where principals and teachers had a positive view of the school climate, including high levels of teacher job satisfaction, expectations for student achievement and parental support."

The report also said that achievement was "highest among students attending schools with few attendance problems."

TIMSS is a project of the International Association for the Evaluation of Educational Achievement based in Amsterdam.