One of the largest feeders for high school math competitions—including those that eventually lead to the IMO—is a middle school program called Math Counts.

高中数学竞赛，包括那些最终通往国际数学奥林匹克竞赛的最大支持者之一是一个叫做“Math Counts”的中学项目。

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The high school curriculum is much higher than the junior middle school, such as Chinese, math, English, physics, chemistry, history, etc... Sometimes I am afraid of seeing so many books in my desk.

高中的课程比初中要多得多，如语文、数学、英语、物理、化学、历史等等。有时后我害怕看到我的课桌里有这么多的课本。

youdao

The classes will be supervised by a high school English teacher, a middle school Math teacher, and former veterinary technician.

FORBES: South Dakota, Internet Learning Pioneer

This program will provide extra help to middle- and high school students who fall behind in reading and math, expand Advanced Placement programs in low-income schools, and invite math and science professionals from the private sector to teach part-time in our high schools.

CNN: Transcript of State of the Union

Designed to spark the interest of middle and high-school girls in science, technology, engineering, and math (STEM) subjects, the Women in STEM Speakers Bureau was launched by the White House Council on Women and Girls and Office of Science and Technology Policy in September of last year.

WHITEHOUSE: STEM Women All-Stars Hit the Road