Coding classes for kids in Juliaca, Peru

The 2017 row is from INEI's Directorio Nacional de Centros Poblados 2017 for Puno, people counted on census day. The 2025 rows are from INEI's Censos Nacionales 2025, Indicadores demográficos, table 1. INEI had not published 2025 figures for cities when we checked in November 2026.

Ages: MINEDU, Edades normativas (normative age measured on 31 March). The coding steps are ours. Hours: MINEDU, CNEB plan de estudios for primaria. When the 2026 school year began on 16 March 2026, MINEDU reported 6,225,000 students in 53,631 schools nationwide.

Course ages, English notes and first projects are ours, based on how children in our classes usually manage.

For a fuller view of coding for this age group across the country, see online coding classes for kids in Peru. Spanish-speaking parents may prefer clases de programación para niños en inglés, which explains the same classes in Spanish.

import csv

sunday = 0
monday = 0
with open("juliaca-epen-2025.csv", encoding="latin-1") as sheet:
    for line in csv.DictReader(sheet):
        sunday = sunday + int(line["C318_1"])
        monday = monday + int(line["C318_2"])
print("Sunday hours:", sunday)
print("Monday hours:", monday)

The error is in English, and the mentor reads it aloud with the children. "Invalid literal for int" means Python was asked to make a whole number out of something that is not one. The two quote marks at the end are the clue: the thing was empty. Babies, school children and people with no job were in those homes too, and nobody asked them about hours, so their boxes are blank. A blank is not the same as zero; it means "no answer".

Version 2 fixes that and a second problem. If a row has no Sunday answer it is skipped. And instead of seven copied lines, one for each day, the column names go into a list, the day names into another list in the same order, and a single loop walks through both.

import csv

columns = ["C318_1", "C318_2", "C318_3", "C318_4", "C318_5", "C318_6", "C318_7"]
days = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"]
hours = [0, 0, 0, 0, 0, 0, 0]
workers = [0, 0, 0, 0, 0, 0, 0]
answered = 0

with open("juliaca-epen-2025.csv", encoding="latin-1") as sheet:
    for line in csv.DictReader(sheet):
        if line["C318_1"] == "":
            continue
        answered = answered + 1
        for i in range(7):
            h = int(line[columns[i]])
            hours[i] = hours[i] + h
            if h > 0:
                workers[i] = workers[i] + 1

print("People who answered:", answered)
for i in range(7):
    print(days[i].ljust(10), hours[i], "hours,", workers[i], "people worked")

Data: INEI, Encuesta Permanente de Empleo Nacional (EPEN) Ciudades 2025, Juliaca file, published on datosabiertos.gob.pe under the Open Data Commons Open Database Licence (ODbL, share-alike). The sums and the ordering are ours. Each person reported the week before their own interview, and interviews ran through all of 2025, so these are not hours for one particular week. They describe the people INEI interviewed, not every worker in Juliaca.

Monday wins, narrowly, so most children were right. The bigger surprise is Sunday: 1,297 of the 3,416 people who answered, about 38%, worked on Sunday as well. For many people in this survey, the working week did not stop at Saturday. Children then ask the next good question themselves: are Sunday workers working fewer hours, or are there just fewer of them? Dividing hours by people answers it, and that is next week's class.

1. Age 6 to 8, unplugged. Ask five people at home how many hours they worked yesterday. Write a dash, not a zero, for anyone who did not work. Why does it matter which you write?
2. Age 8 to 10, in Scratch. Make two lists, one of day names and one of numbers, and have a sprite say each day with its number. Use one loop, not seven blocks.
3. Age 10 to 12, in Python. Run Version 1 and read the error aloud. Fix it yourself before you look at Version 2.
4. Going further. Divide each day's hours by its number of workers. On which day do the people who work, work longest?

Peru keeps UTC minus 5 hours throughout the year and has not changed its clocks since 1994 (tz database zone America/Lima; INACAL publishes the official hour). India keeps UTC plus 5 hours 30 minutes, so the gap is always 10 hours 30 minutes.

Since neither country moves its clocks, a slot booked now is the same slot next year. Book in Juliaca time and the system converts it for the mentor. Many families pick a morning class in the January to March holidays and keep it, or move it to the afternoon, once primaria restarts in March.