Coding Classes in Leidschendam-Voorburg

Course picks for Leidschendam-Voorburg

Four courses for the town of Hofwijck and the Vliet

A child in Stompwijk who wants to make a ball bounce on screen, a teenager in Voorburg writing a first physics game, a student in Leidschendam modelling something that changes over time, and an adult whose spreadsheets project a figure forward month by month. The first lesson is free for each of them.

Ages 8 to 12

Game Development for Kids

Moving objects in games, where a child sees a bouncing ball bounce a little higher each time and learns to find out why.

See the syllabus

Ages 11 to 14

Maths Through Coding

Mathematics made concrete in code, including step-by-step models of motion and growth and the errors they carry.

See the syllabus

College and adult

Python Automation Course

Python simulations built with a check that the quantity which should stay constant actually does.

See the syllabus

Adults

Data and AI Analytics for Non-Programmers (Excel, Sheets, Power BI)

Forecasts rolled forward period by period, tested for the small repeated error that grows into a large one.

See the syllabus

Browse the course atlas for more than one hundred options and use the coding roadmap to check prerequisites.

The four we are known for

Python, AI, vibe coding and agentic coding

These run underneath everything above. Every one is live and online, placed by ability rather than by age, and the first class is free.

Vibe codingAges 13 to 17

Vibe Coding for Teens

Python, web and AI projects where the learner still owns the thinking.

See the syllabus

Python and AICollege and adult

Python Automation Course

Automate the work you already do, then let AI carry part of it.

See the syllabus

AI and MLAges 14 to 18

AI and Machine Learning for Teens

Train a model, read what it learned, and be able to say why it is wrong.

See the syllabus

Agentic codingProfessionals

Codex & Claude Code

Run AI coding agents on real work without losing control of the codebase.

See the syllabus

Leidschendam-Voorburg today

Two towns merged in 2002, a Roman forum, and a canal down the middle

The present municipality was created on 1 January 2002 by merging Leidschendam and Voorburg, and at the same time almost the whole of the Tedingerbroekpolder was annexed by The Hague. The Rijn-Schiekanaal, better known as the Vliet, cuts through the municipality from south-west to north-east. The statistics office counts two woonplaatsen, 13 wijken and 43 buurten, on 3,261 hectares of land within 3,562, a published density of 2,402 residents to the square kilometre.

Forum Hadriani

Under Voorburg the Romans founded a civil town. As the name Forum Hadriani shows, forum meaning market place, it was a place of trade, and the emperor Hadrian attached his name to it in 121 on his journey through the region. Around 161 it took another name, Municipium Aelium Cananefatium, the capital of the Cananefates.

Hofwijck

Hofwijck, an estate dating from 1642 in Voorburg, was designed by Constantijn Huygens with Jacob van Campen. Constantijn and his son Christiaan lived there in the seventeenth century; in 1692 Christiaan described experiencing the earthquake of Verviers at Hofwijck. Since 1914 it has been a museum, and it now holds an exhibition on the Huygens family.

Voorburg and its church

The Oude Kerk, also called the Sint-Martinuskerk, is a Gothic church from around 1200. Voorburg itself had 43,090 residents on 1 January 2023, according to its encyclopaedia entry, which also names the neighbourhood of Essesteijn.

Christiaan Huygens and the pendulum clock

In 1656 Christiaan Huygens held a patent on the first pendulum clock, which was built by Salomon Coster in The Hague. Astronomy, and finding position at sea, required accurate measurement of time, which led Huygens to the problem, and in his Horologium Oscillatorium of 1673 he set out the theory of the motion of a pendulum. He died in The Hague on 8 July 1695.

A simulation that drifts

A 20-degree swing, stepped forward two ways

The figures in this table were computed for this page, with a standard program, for an ideal 1 metre pendulum released at 20 degrees under gravity of 9.81 metres per second squared. They describe the program, not any clock or any real pendulum.

Largest swing in the seconds before each mark, by stepping rule and step size
Stepping rule and step	After 10 seconds	After 30 seconds	After 60 seconds
Explicit Euler, 0.01 s steps	31.1 degrees	78.8 degrees	spinning over the top; energy about 41 times the start
Explicit Euler, 0.001 s steps	20.9 degrees	23.1 degrees	26.7 degrees; energy about 1.8 times the start
Semi-implicit Euler, 0.01 s steps	20.0 degrees	20.0 degrees	20.0 degrees; energy within about 1 percent
Semi-implicit Euler, 0.001 s steps	20.0 degrees	20.0 degrees	20.0 degrees; energy within about 0.1 percent

The two rules differ by a single choice: whether the new angle is computed from the old speed or from the speed just updated. Explicit Euler, the rule most people write first, uses the old speed, and for a swinging system that makes every step add a little energy. Making the steps ten times smaller slows the drift a great deal and does not stop it; after a minute the swing has still grown from 20 to almost 27 degrees. Semi-implicit Euler uses the updated speed, and its errors wobble around the true answer instead of piling up, so the swing stays at 20 degrees however long the program runs. Neither rule is exact. The difference is that one makes errors which cancel and the other makes errors which add, and over thousands of steps that difference is everything.

Verified local facts

The municipality in the national statistics

Figures for Leidschendam-Voorburg as the national statistics publish them, with the year of each; the history from the encyclopaedia; and the calculations made here, listed at the end.

A population that dipped and rose

On the present boundaries the count was 74,058 in 1995, 72,588 in 2013 and 78,916 in 2026, with 78,318 in 2025. The page makes no claim about why the count fell and then rose. Women outnumbered men in 2025, 40,626 to 37,692.

Ages in 2026

12,233 were under fifteen, 7,997 between fifteen and twenty-five, 19,528 between twenty-five and forty-five, 20,505 between forty-five and sixty-five, and 18,653, almost a quarter, sixty-five or older.

Households

In 2025, 37,719 households averaged 2.05 people; 15,804 consisted of one person and 11,820 included children.

Homes and income

37,861 dwellings in 2025, of which 22,338 owner-occupied and 15,523 rented, with an estimated average value of 443,000 euro. Income averaged 40,400 euro per resident and 49,800 per income recipient in 2024; 3.3 percent of residents were in poverty.

Schools and origin

21 primary establishments taught 5,858 pupils, some 279 each, and 7 secondary establishments 4,811, some 687 each, with 697 MBO students at institutions in the municipality. In 2025, 60,361 residents had been born in the Netherlands; by origin 48,362 were Dutch, 8,794 European and 21,162 from outside Europe.

What was worked out here

78,916 less 72,588 is 6,328, and 78,916 less 74,058 is 4,858. 5,858 pupils over 21 establishments is about 279, and 4,811 over 7 about 687. The origin groups, age groups and tenure groups were each summed to check nothing is missing. The pendulum table was computed separately and is described above.

Modern Age Coders has no link of any kind with the municipality, Hofwijck, the Huygens family's heirs or any school in Leidschendam-Voorburg, and the page suggests none. The statistics are those published for the municipality in the years given, with earlier years recalculated to the present boundaries. The merger, the Tedingerbroekpolder and the Vliet come from the encyclopaedia entry for the municipality; Forum Hadriani, the Oude Kerk and Voorburg's population from the entry for Voorburg; the estate from the entry for Hofwijck; and the pendulum clock from the entry for Christiaan Huygens. The municipal entry gives 78,915 residents for 1 January 2026, which is not combined with the statistics used here.

Signature project

Watch the quantity that should never change

Every simulation that steps forward in time makes a small error at each step. The question is not whether there is error but which way it points, and there is almost always a simple way to find out.

1. Find the conserved quantity

Most physical systems keep something constant: energy for a frictionless pendulum, total money in a closed ledger, the number of people in a population model with no births or deaths. Write down what should stay fixed.

2. Log it every step

Compute that quantity at every step and plot it. In a correct simulation it wobbles slightly around a flat line. If it climbs or falls steadily, the errors are adding up in one direction.

3. Change the method, not just the step

Smaller steps delay a drift and cost time. A better method, such as updating the speed before the position, can remove the drift altogether. Test both, and keep the one whose conserved quantity stays flat.

Small errors that point the same way
Where it happens	The step	What drifts	How it shows
A game with physics	one frame of movement	energy	a ball that bounces higher each time, or a character flung off the map
A robot or car simulator	one simulated tick	position and speed	a trained controller that works in simulation and fails on the real machine
A running total in money	each rounded transaction	the balance	cents that appear or vanish over thousands of operations
A forecast rolled forward	each month built on the last	the trend	a small bias that becomes a large gap after a few years
The pendulum on this page	one hundredth of a second	energy, with explicit Euler	a 20-degree swing that becomes a spin within a minute

Why AI trained in simulation needs this lesson

Robots, self-driving systems and many game-playing AIs are trained largely inside simulators, because a simulator can run millions of trials safely and cheaply. Every one of those simulators steps its world forward in small increments, and each increment carries a small numerical error. If those errors point the same way, the simulated world slowly behaves unlike the real one: objects keep a little energy they should lose, contacts are slightly too springy, a vehicle travels a fraction further than it would. An AI that learns to exploit such quirks can perform brilliantly in simulation and badly in reality, which engineers call the gap between simulation and the real world. The first defence is exactly the one on this page. Decide what should stay constant or match reality, measure it at every step, and choose methods whose errors cancel rather than accumulate. A pendulum is the smallest possible example, and the one Huygens, who worked on its theory in the house on the Vliet, would have understood best.

Reliable pipeline

Five checks for any program that steps through time

For games, physics, population and money models, forecasts and AI training environments. Built around a pendulum, in the town where the theory of pendulum motion was lived with.

Keeping step-by-step programs honest
Check	How	The failure it catches	What you gain
A conserved quantity	Pick something that should not change and compute it each step	Errors accumulating silently	An alarm that rings early
Two step sizes	Run with a step and with a step ten times smaller, and compare	Results that depend on the step	A measure of numerical error
A better method	Try an update order or integrator suited to the system	Drift that smaller steps only delay	Stable long runs
A known answer	Test against a case with an exact solution, such as a very small swing	Code that is wrong everywhere	Confidence in the basics
A long run	Run far longer than you need and look at the end	Problems that appear only after many steps	Behaviour you can trust over time

For younger learners

A bouncing ball in a game that should bounce to the same height every time. The child notices it creeping higher, counts the bounces, and swaps two lines of code to fix it.

For teenagers

A pendulum simulated in Python with both Euler rules, energy plotted over a minute. The teenager reproduces the drift, then explains in one paragraph why one line in a different order stops it.

For adults

A spreadsheet forecast rolled forward month by month, checked by running it with a small deliberate error and watching how far it travels. Adults often find the model amplifies errors they had assumed were harmless.

This section uses the encyclopaedia's account of Christiaan Huygens and Hofwijck as the setting, and a pendulum simulation computed for this page with standard methods. It says nothing about any real clock, and nothing about how Huygens himself calculated.

Learning ladder

From a ball that bounces too high to a simulation that stays true

Placement comes from watching the learner work in the free lesson on a real task. It does not come from age on its own, nor from whether home is Voorburg or Stompwijk.

Ages 6 to 10

The creeping bounce

Children spot a game ball bouncing higher each time and fix it.

Scratch Coding for Kids Game Development for Kids

Ages 11 to 13

Step by step

Learners move an object through time in small steps and count the error.

Python and AI for Kids Maths Through Coding

Ages 14 to 18

Two Euler rules

Teenagers simulate a pendulum both ways and plot the energy.

App Development for Teens Data Science for Teens

Ages 18 to 67

Rolled-forward models

Adults test a forecast for errors that grow as it steps ahead.

Python Automation Course Data and AI Analytics for Non-Programmers (Excel, Sheets, Power BI)

Coding and AI

An AI can write a physics simulation in seconds. Why should a teenager in Voorburg check that its pendulum does not speed up?

Because the simplest correct-looking code drifts, and the drift only shows if someone looks for it.

Ask an AI assistant for a pendulum, a bouncing ball or an orbit and it will usually produce clean, readable code using the most familiar stepping rule, the one every textbook shows first. It runs, it animates, and for the first few seconds it looks right. Whether it stays right over a thousand swings depends on a choice the assistant may never mention, and a quick demo will not reveal it. The same pattern appears in larger systems, where AI-written simulations feed games, training environments and forecasts that run for a very long time.

A learner who has watched a simulated pendulum climb from 20 degrees to a full spin, and then fixed it by swapping the order of two lines, knows to ask what a simulation should conserve and to measure it. That habit decides whether a program can be trusted over long runs, and no amount of fluent code replaces it. The model can write the loop. Checking that the loop keeps faith with reality is a human responsibility.

So the case for a child in Leidschendam-Voorburg learning to code in 2026 is not Hofwijck or its famous residents. It is that someone who watches the quantity that should never change will be needed wherever AI builds simulated worlds and trains machines inside them. The longer argument is in why a child should still learn to code in 2026.

Delivery

Classes on both banks of the Vliet

The municipality stretches along the Vliet from the Hague border to the polders of Stompwijk, and a learner anywhere along it joins the same class from home.

No crossing required

A pupil on one side of the Vliet and a pupil on the other open the same lesson at the same moment. Nobody needs a lift over a bridge on a school night.

School words as they are

The brugklas, vmbo, havo, vwo, groep and profielkeuze of a Zuid-Holland school keep their Dutch names; everything around them is explained in English.

A free lesson, properly taught

The first session is a full lesson on a real problem. The teacher observes how the learner works and afterwards recommends a level, a course and a weekly time, taking no payment details.

Five to ten at one stage

Groups are built from learners at the same point. The municipality has 12,233 residents under fifteen, but a matching five, free at the same hour, is uncommon, so groups can draw on learners in other countries.

Regio Midden breaks

Classes meet twice weekly, about eight times a month, in the same slot, and pause during the regio Midden holidays that Zuid-Holland schools follow.

Teachers in India

With the teaching team three and a half hours ahead of Dutch summer time and four and a half ahead in winter, afternoon, evening and weekend-morning classes all fit.

Twenty-eight schools, and a group that forms online

Leidschendam-Voorburg has 21 primary establishments teaching 5,858 pupils and 7 secondary establishments teaching 4,811. A coding group needs five learners who agree on subject, stage and hour at once, and they are far easier to gather across every age from 6 to 67 and many countries than within one municipality.

Fees

Fees for Leidschendam-Voorburg families

The complete price list is these three lines.

First classUSD 0

A real lesson built round a real task, with a level and a course at the end.

Group tuitionUSD 100

Per month, normally eight classes, in a group of five to ten learners at one level.

Private tuitionUSD 150

Per month, normally eight classes, with one teacher for one learner.

The dollar price is the same in every country, with no euro table beside it, so a family in Stompwijk pays exactly what a family in Voorburg pays. Nothing is due until the free lesson has settled the course and the time, and payment is arranged over WhatsApp after that. The pricing page explains pauses, a change of format and missed classes.

Request placement Check availability

Reviews

Six Google reviews in their authors' own words

Rated 4.9 across 547 Google reviews. These are real reviews, reproduced as written.

★★★★★

"The one step solution for my son. Modern Age Coders make learning coding so simple that kids love it. The teachers explain complex concepts clearly with practical exercises and interactive content."

Ria Mukherjee

Parent

★★★★★

"Modern Age Coders has been a game-changer for me. I struggled to grasp IT concepts and coding before joining, but their classes transformed everything. I can now confidently write complex programs with ease."

Samriddha Mondal

Student

★★★★★

"One of the most wonderful education centres out there. Education is not limited to school syllabus but focuses on skill development."

Vansh Agarwal

Student

★★★★★

"My child Dhairya is really enjoying the Modern Age Coders classes. This is his first online class and he eagerly looks forward to it. I can already see his improvement, and the teachers are very cooperative."

Sonam Oswal

Parent of Dhairya

★★★★★

"Modern Age Coders have wonderful teachers who teach in a clear, easy and practical way. The teacher boosts students' confidence and inspires them to learn without hesitation."

Sonu Goyal

Parent

★★★★★

"I highly recommend this computer coding class! The teachers are incredibly knowledgeable and passionate about coding."

Ritu Kedia

Parent

Free placement class

Tell us where the learner is starting

The first task might be a ball that bounces a little too high, an object moved through time in small steps, or a pendulum simulated two ways with its energy on a chart.

FAQ

Leidschendam-Voorburg coding class questions

The merger, the Romans, Hofwijck, the figures, and the lessons.

When was Leidschendam-Voorburg formed?

On 1 January 2002, by merging Leidschendam and Voorburg. At the same time almost the whole of the Tedingerbroekpolder was annexed by The Hague. The statistics office counts two woonplaatsen, 13 wijken and 43 buurten.

How many people live in Leidschendam-Voorburg?

The national count was 78,916 on 1 January 2026, in 37,719 households in 2025. On the present boundaries the count was 74,058 in 1995 and 72,588 in 2013.

What was Forum Hadriani?

A Roman civil town under present-day Voorburg, a place of trade to which the emperor Hadrian attached his name in 121, according to the encyclopaedia. Around 161 it was renamed Municipium Aelium Cananefatium, the capital of the Cananefates.

What is Hofwijck?

An estate in Voorburg dating from 1642, designed by Constantijn Huygens with Jacob van Campen. Constantijn and his son Christiaan lived there in the seventeenth century, and since 1914 it has been a museum; it now houses an exhibition on the Huygens family.

What did Christiaan Huygens have to do with clocks?

In 1656 he held a patent on the first pendulum clock, built by Salomon Coster in The Hague, and in 1673 he published the theory of pendulum motion in his Horologium Oscillatorium, according to the encyclopaedia.

How many schools are there in Leidschendam-Voorburg?

The statistics list 21 primary establishments with 5,858 pupils and 7 secondary establishments with 4,811, plus 697 MBO students at institutions in the municipality. No school is rated on this page.

What language are the classes in, and when can they be taken?

Classes are taught in English, and Dutch school terms such as brugklas, havo and vwo are kept in Dutch. Because the teachers work three and a half hours ahead of the Netherlands in summer and four and a half in winter, afternoon, evening and weekend slots are all possible. The slot is agreed in the free lesson, and the regio Midden holidays are kept.

Is there a Modern Age Coders classroom in Leidschendam-Voorburg?

No, and none is claimed here or anywhere in the Netherlands. All teaching is live and online and needs a laptop or desktop, working audio, a current browser and a connection that holds. The telephone number shown on this page is an Indian one and is described as such.

What do Leidschendam-Voorburg coding classes cost?

The first lesson is free. After it, group tuition is USD 100 a month for two live lessons a week, normally eight across the month, in a group of five to ten learners. One-to-one tuition is USD 150 a month at the same frequency with a single teacher. Course, format, recurring hour and availability are all confirmed before anything is paid.

How many learners are in a group?

Five to ten, matched on level, pace and goal rather than on age, school or address. One-to-one means a single learner with a single teacher. When no group at the right level is running, a family can take one-to-one lessons or wait for the next group to form.

Explore Haaglanden and beyond

Into The Hague, along the Vliet, and out to the province

The capital next door has its own page at coding classes in The Hague, with district pages including Leidschenveen-Ypenburg. Along the Vliet lie Leiden to the north-east and Delft to the south, and the whole province is on Zuid-Holland. A learner heading straight for machine learning can go to the AI and Python Academy, and the full series is on the Netherlands coding hub.

Book the free class Send us a WhatsApp

Four courses for the town of Hofwijck and the Vliet

Game Development for Kids

Maths Through Coding

Python Automation Course

Data and AI Analytics for Non-Programmers (Excel, Sheets, Power BI)

Python, AI, vibe coding and agentic coding

Vibe Coding for Teens

Python Automation Course

AI and Machine Learning for Teens

Codex & Claude Code

Two towns merged in 2002, a Roman forum, and a canal down the middle

Forum Hadriani

Hofwijck

Voorburg and its church

A 20-degree swing, stepped forward two ways

The municipality in the national statistics

A population that dipped and rose

Ages in 2026

Households

Homes and income

Schools and origin

What was worked out here

Watch the quantity that should never change

1. Find the conserved quantity

2. Log it every step

3. Change the method, not just the step

Why AI trained in simulation needs this lesson

Five checks for any program that steps through time

For younger learners

For teenagers

For adults

From a ball that bounces too high to a simulation that stays true

The creeping bounce

Step by step

Two Euler rules

Rolled-forward models

An AI can write a physics simulation in seconds. Why should a teenager in Voorburg check that its pendulum does not speed up?

Classes on both banks of the Vliet

No crossing required

School words as they are

A free lesson, properly taught

Five to ten at one stage

Regio Midden breaks

Teachers in India

Fees for Leidschendam-Voorburg families

Six Google reviews in their authors' own words

Tell us where the learner is starting

Leidschendam-Voorburg coding class questions

When was Leidschendam-Voorburg formed?

How many people live in Leidschendam-Voorburg?

What was Forum Hadriani?

What is Hofwijck?

What did Christiaan Huygens have to do with clocks?

How many schools are there in Leidschendam-Voorburg?

What language are the classes in, and when can they be taken?

Is there a Modern Age Coders classroom in Leidschendam-Voorburg?

What do Leidschendam-Voorburg coding classes cost?

How many learners are in a group?

Into The Hague, along the Vliet, and out to the province

Keep exploring Modern Age Coders

Coding classes in nearby places

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