WASHINGTON -- Hey kids, grabs those beakers and Petri dishes, the White House is going to hold a science fair.

President Obama said Monday he would convene a national science fair next year to honor young inventors with the same gusto that college and professional athletes celebrate their victories at the White House.

"You know, if you win the NCAA championship, you come to the White House," said Obama, a sports fan as much as a science nerd. "Well, if you're a young person and you produce the best experiment or design, the best hardware or software, you ought to be recognized for that achievement, too. Scientists and engineers ought to stand side by side with athletes and entertainers as role models."

He said they would show young students how "cool science can be." He noted $260 million in companies' donations to take science into more classrooms with television programs and celebrity science personalities.

The president made his remarks as he decried what he described as students' lagging performance.

"Now, the hard truth is that for decades we've been losing ground," Obama said. "One assessment shows American 15-year-olds now rank 21st in science and 25th in math when compared to their peers around their world."

But Obama ignored another set of tests showing that fourth- and eighth-graders are holding their own and even making gains on kids in other developed countries.

Obama cited a test given to 15-year-olds in 30 developed countries, the Program for International Student Assessment, or PISA. Some experts caution that PISA is different from other tests, especially those in the United States, and makes American kids look worse than other tests do.

But other tests show that while U.S. kids trail those in a handful of high-achieving Asian countries -- Singapore, Taiwan and Japan -- they hold their own in the larger group of developed countries that comes next.

In fact, the United States has gained on some of its toughest competitors since 1995, making bigger strides in math than Singapore and Japan, and in science than Japan.

That's according to the Trends in International Mathematics and Science Study, or TIMSS. Researchers involved in TIMSS say the United States is not trailing the developed world by any stretch of the imagination.