The lesson is geometry, but the language is not Euclid's: ''Given two socialist countries, when the path of one of the countries is crossed by the path of a capitalist country, what is the effect on the second socialist country?''
The correct answer, for budding socialists at least, is, ''The same effect as on the first country.'' The exercise illustrates both political theory and the geometrical theorem that a line intersecting two parallel lines forms congruent angles.
Education, with a definite political tinge, is becoming institutionalized once more in Kampuchea (Cambodia).
When the Khmer Rouge came to power in April 1975, leader Pol Pot closed the schoolroom doors in one fell swoop. To express his contempt for formal education , schoolhouses were turned into piggeries or communal kitchens. One high school in Phnom Penh became the infamous Tuol Sleng prison and torture chamber, where 16,000 top-ranking cadres and intellectuals were killed.
The closures were intended to be permanent. But three years ago this month Pol Pot and his regime, Democratic Kampuchea, were ousted by the invading Vietnamese. The new government headed by Heng Samrim has focused its attention on education, and schools are quickly re-opening in the villages.
The government has issued itself an impressive report card. In the first half of last year, 221 kindergartens opened and 411,250 adults were taught to read. Kompong Cham, one of the most populous rural provinces, now boasts 21/2 times as many teachers as it had before 1975.
The government has reason to make haste. Schools not only offer reading, writing and arithmetic, but also form a cornerstone of political education directed toward building a supportive citizenry.
In the provincial town of Kompong Chhnang, the first-grade classroom is plastered with four admonitions: ''Do not listen to enemy propaganda; do not serve the enemy; do not shelter the enemy; do not follow the enemy.''
Who, a visitor asks, is the enemy? ''Pol Pot,'' the children reply without hesitation. They are not just denigrating an ousted leader; guerrillas of the Khmer Rouge, recognized by the United Nations as Kampuchea's government, are seeking to destabilize the Heng Samrin regime.
Provincial authorities report that 70 to 80 percent of school-age children attend classes. While many schools have been repaired, often with donated labor and materials, the shortage of teachers has been more difficult to overcome.
Kampuchea's educated class suffered heavily under the Pol Pot regime. Few of those who did not conceal their education survived. Since 1979, many of the surviving middle class and educated have left, seeking new lives in the West.
In the Mrome subdistrict of southern Kampot province, only two of 28 former teachers survived Pol Pot. One of them, Pa Neak, is now in charge of education and culture on the People's Revolutionary Committee.
''Our primary responsibility is to direct teachers along the correct line of our revolution. Secondly, we must try to make people recognize and abandon bad culture,'' he says.
To get students back to school as quickly as possible, the government has shortened teachers' training. In Pa Neak's district, 30 kindergarten teachers were trained for one week and began teaching the day after ''graduation.'' The government had agreed to pay 12 of them the standard salary equivalent to about rice for the year.
For older children lacking the basics, a condensed curriculum speeds them through school. Political education is administered in regular doses to government workers.
With the guidance of the Ministry of Education, schools also seek to cultivate a love of manual labor. When not reciting lessons, students weed the school's vegetable patch, sweep the yard or re-thatch the roof.
The same belief in the benefits of manual labor is seen outside the schools. When the Mekong River threatened to overflow its banks last summer, doctors and nurses were plucked from hospital wards in Phnom Penh and dispatched with others to reinforce dikes.
Formal education gradually filters upward to the secondary levels. Last year the Kampuchea-Soviet Friendship Institute, a technical school, admitted 335 students. The reopened medical school graduated its first class of doctors in November.
Meanwhile, the cream of the student crop is skimmed off for specialized training overseas. About 300 are studying in the Soviet Union, and 700 in Eastern Europe, according to the Foreign Ministry. The ministry itself is preparing to send 25 young cadres to study English in India.