Mexico's preschools are often located in private homes in residential neighborhoods. The federal Ministry of Education licenses such schools when they have met certain health and safety standards; many operate without a license.
Usually their only source of income is the monthly fees paid by parents. But the Salzburgo preschool I visited in the Narvarte district here in the nation's capital had a plaque proudly proclaiming its gratitude to a private benefactor. Tuition in this school is 26,000 pesos (about $160) a year.
Miss Angelita, the owner-director, is proud of the fact that all five of her teachers have been pedagogically trained. One teacher, referred to as Miss Toni, gives daily, half-hour classes in English to every class.
Public speaking is considered an important skill at this preschool. I watched two Mexican children in the youngest group (2- and 3-year-olds) give a talk about airplanes. They had a poster on which three pictures of planes had been mounted.
A muchacha (girl) showed which plane was a Concorde and said she had been to the airport and had seen airplanes. A muchacho (boy) said his uncle was a pilot. He also showed the remnants of an airplane ticket and said you must have a ticket to ride on an airplane.
Neither child seemed intimidated by the 80 children squeezed into the former living room, which had been transformed into an assembly area. This was true even though the oldest children at the school are 6 and loom above the little ones like giants.
Nor did any of the older children belittle the toddlers' performance. Those children whose attention appeared to be flagging during the talk were immediately brought to order by the teaching staff positioned strategically in their midst.
All ages can sing the Mexican national anthem. On Mondays, all pupils must come dressed in white for the flag-raising ceremony. They are not allowed to enter school after the ceremony has begun. ''This is to educate the parents to the necessity for promptness,'' Miss Angelita explained.
The school's equipment is comparable to that found in good preschools in the United States. All of it is neatly stored on shelves behind plastic curtains. The shelves hold musical instruments, costumes, large blocks, puzzles of varying levels of difficulty, puppets, measuring jugs, Montessori-type letters.
A live rooster occupies a cage on the playground. A little pupil-propelled carousel has five brightly painted wooden animals, which the fastest children scurry to mount while the others vie for floor space. Also on the playground is a fully equipped playhouse with two toy tele-phones.
The youngest children have small tables and chairs for construction projects in the former garage. Although very crowded, the space is shaded and airy. (Many middle- and upper-class Mexican parents do not want their children's skins to tan too much: Light skin suggests a colonial rather than an indigenous background and is something of a status symbol. I noticed how many of the children in Miss Angelita's school had blond or light-colored hair and that she herself was blond.)
When I visited, the smallest children were making toy radios. The teacher constructed a little box from paper for each child. The children then painted the entire box red and glued on two buttons for knobs and a small gingham circle for a speaker.
The part they liked best was jabbing in a toothpick as an antenna. Like all children, Mexican youngsters can think of other jabbing possibilities when armed with toothpicks, so the teacher was kept busy trying to prevent personal injuries.
The oldest children sit two to a desk in rows in a traditional classroom on the second story of the house. Their room has a large blackboard and a bulletin board filled with English ''dictados'' (spelling lists of words orally dictated by Miss Toni). But most of their instruction takes place in Spanish.
Mexican law requires children to have completed one year of kindergarten before they enter primary school at age 7. The kindergarten at this school is more like first grade in the US. It offers formal instruction in reading, writing, and arithmetic. The classes, however, are more formal and serious than first grade in most American schools.
Miss Angelita looked affronted when asked if children enter public school after completing her course of instruction.
''No, never,'' she replied emphatically. ''The public schools are poor; our children enter good private schools.
''Because of the economy, we have only 80 here this year. Last year we had 120.''
Some children are shuttled from home to school on successive trips made by the school's official driver. There seemed to be more little pupils per car than American standards would allow. Other children are chauffeured by their parents. Car pools do not seem to be very popular, perhaps because families, rather than neighborhoods, are the basis of social organization in Mexico.
The school opens at 9 a.m. and closes at 1 p.m. There is no rest period; children bring a snack or sandwich to eat at 11:30.
The last North American preschool I visited had acres of grass; large paved areas for tricycles and wagons; a caged skunk, from which it was wise to keep one's distance; and spacious classrooms. But its suburban location had a very different population base than Mexico City, which now houses 18 million people, half of whom are under age 15.
For the same reasons that nursery schools and kindergartens have achieved popularity in the US, many middle- and upper-class parents here enroll their children in such private jardins de ninos.
Considering the increasing demand for preschools and the space-per-person problems of this metropolis, overcrowding is not surprising. And perhaps the most needed lessons for children growing up in such urban congestion would include how to behave in a civil manner where the ratio of people to space is very high.