Classroom Management

Classroom Management

Practical advice for running Geometry Playground in a real classroom: device logistics, workflow between lessons, differentiation, and what to do when things go sideways.

This page is for teachers who have already read Setup and Overview and are now ready to think about day-to-day operations.

At a glance

Class size	Works for 15 to 30 students. Bigger classes need pair programming.
Device model	1:1 iPads ideal. Pairs at a shared iPad also works.
Lesson length	50 to 60 minutes per session. Minimum 40.
Teacher prep	10 minutes per lesson after the first week.

Device setup for the first lesson

Before students touch the iPads, you need:

1. Swift Playgrounds installed on every device (see Setup).
2. The Geometry Playground book subscribed on every device.
3. A projector or screen mirror so you can demonstrate from the front.
4. A plan for where students sit. Top-down camera work is easier when students can see each other's screens.

First lesson pacing. Spend the first 15 minutes just getting everyone into the app, logged in, and looking at Chapter I, section 1. Don't try to teach content on the first day. The goal is "everyone can open the book and find the tutorial". If you achieve that, the first lesson is a success.

Adding new pages for each exercise

Swift Playgrounds lets you add extra pages inside a book. This is one of the most useful features for a classroom, and it's worth teaching students how to do it from lesson two onwards.

Why it matters. Each exercise in Geometry Playground is a single page with starter code, instructions, and a canvas. If a student wants to experiment, or try a variation, or rewrite a solution from scratch, editing the original page loses the starter code. Adding a new page gives them a scratch space.

How students add a page:

1. Tap the + button in the top toolbar (in the playground view).
2. Swift Playgrounds adds a blank page after the current one.
3. The student can copy code from the exercise page into the new page and modify it freely.
4. The original exercise page remains untouched for reference or re-reading.

Classroom rules you might set:

• "Always work the exercise on the original page first. Only add a new page if you want to experiment or extend."
• "Name your extra pages clearly: 'My Star', 'Bigger House', 'Fence Variation'."
• "If you get stuck, delete your extra pages to reduce clutter, but never delete the original exercise pages."

Teacher tip. During class, walking around and seeing the extra pages students have added tells you more about their engagement than any formal assessment. A student with five extra pages of variations is a student who has caught fire. A student with zero extra pages might need a nudge.

If you aren't in an Apple environment

Geometry Playground is built for Swift Playgrounds on iPad, but the ideas travel. If your school uses Chromebooks, Windows laptops, or anything else, you can run the same curriculum using Python turtle.

What is Python turtle? A drawing library built into Python. You tell a virtual turtle to walk forward, turn left, and lift its pen. It draws on the screen as it moves. The walking metaphor is identical to the one this curriculum uses, which makes it a near-perfect substitute.

How to adapt:

• Setup: Install Python (free, cross-platform) or use an online editor like trinket.io or replit.com which need nothing more than a web browser.
• Chapter I (Coordinate Geometry with Sequences): Python turtle has forward(), right(), left(), penup(), pendown(). Every Chapter I exercise translates directly.
• Chapter II (Shape Properties with Variables): Python variables work identically. side = 50 followed by forward(side) behaves the same way.
• Chapter III (Polygon Patterns with Loops): Python for i in range(n): replaces Swift's for _ in 0..<n. The loop body is the same.
• Chapter IV (Sorting Shapes with Conditionals): Python if / elif / else replaces Swift's if / else if / else. The logic is identical.
• Chapter V (Similarity with Functions): Python def drawStar(size): replaces Swift's func drawStar(size: Double). Drop the type annotation and you're done.
• Chapter VI (Composite Figures in Action): Composition works the same way. A main routine calls several smaller functions.

What you lose: the polished Swift Playgrounds interface, the touch-first editing, the curated canvas. Python turtle is bare bones.

What you gain: Python is arguably more useful as a long-term language for students. If your school is already teaching Python in senior years, using turtle for Year 9 geometry is a clean on-ramp.

Recommendation. Read through the exercises on the companion site and port them by hand as you go. Don't try to convert the whole curriculum up front; it's faster to adapt lesson by lesson.

There's no official Python version of Geometry Playground, and no plans to build one. If a teacher in a Chromebook school wants to write a Python port, contact me via the Home page and I'll happily link it.

Save state between lessons

Swift Playgrounds saves automatically. Students' work persists on the iPad across lessons, including extra pages they've added and edits to existing pages. You don't need to do anything to "save" at the end of a lesson.

The gotcha. Save state is per-device, not per-student. If you have a trolley of shared iPads and students don't use the same one every lesson, their work vanishes from their point of view. There are three ways around this:

1. Assign a specific iPad to each student for the duration of the unit. Simplest and best. Put a sticker with the student's name on each iPad.
2. Use Shared iPad mode with student Apple IDs. Works, but needs Apple School Manager and an MDM. See Setup.
3. Don't worry about losing work. Every exercise is self-contained. A student who loses their progress can open the exercise page, see the starter code, and begin again. The curriculum is designed to tolerate this.

If you're new to this, start with option 1. It's the pragmatic choice in most Australian state schools.

Pair programming versus solo work

Solo work is better when:

• Every student has their own iPad.
• The exercise is a drill (Chapter I sections 2 to 6, Chapter III sections 4 to 6).
• Students are confident and moving at different paces.

Pair programming is better when:

• iPads are shared (two students per device).
• The exercise is conceptual (Chapter II Variables tutorial, Chapter V Functions tutorial, Chapter VI Neighbourhood Scene).
• Students are nervous or unsure.
• You want a student who gets it to teach a student who doesn't.

The pair programming protocol. One student is the driver and holds the iPad. The other student is the navigator and watches the screen and suggests what to type. Swap roles every 10 minutes. The driver must type exactly what the navigator says, even if they think it's wrong. If they disagree, they discuss it before typing. This is a professional software engineering technique and it transfers directly to the classroom.

When it fails. Some pairs never gel. A dominant student takes over; a quiet student disengages. Watch for this and split them up on the next lesson.

Differentiation

Geometry Playground is deliberately spiky in difficulty. Most exercises are routine; a few are genuinely hard. That means almost every lesson has natural differentiation built in: the fast students do the hard exercise, the slower students do the drill exercises and consolidate.

For fast finishers: every chapter's teaching notes page has an "Extensions for fast finishers" section. See Chapter I and the others. These extensions are not in the main book; they're prompts for students to invent something of their own.

For students who are struggling:

• Go back one section. Almost every hard section depends on the previous one; the fix is usually upstream.
• Pair them with a student who just finished the same exercise. Peer teaching is fast and effective.
• Drop the hardest exercises. You can skip Chapter II section 16 (Letter Z) or Chapter V section 13 (Filled Star) without breaking the sequence.
• Let them work the exercise on paper first. Some students need to see the geometry before the code.

For students with accessibility needs:

• Swift Playgrounds supports iPadOS accessibility (VoiceOver, Zoom, Dynamic Type).
• The companion site has a font size slider, high-contrast mode, and a vocabulary glossary. See the Library API page for what's available.

Managing absences

A student misses a lesson. What do they do?

Easy case: the lesson was a drill exercise. They open the book, find the section, and do it on their own time. Ten minutes.

Medium case: the lesson was a tutorial that introduced a new concept. They read the exercise page (which includes the explanation in the top panel), watch a classmate, or ask you for a 2-minute demo at the start of the next lesson.

Hard case: the student missed a key conceptual lesson (Chapter II Variables tutorial, Chapter V Functions tutorial). Don't let them skip. Either catch them up one-on-one or pair them with a confident student for the next lesson.

The best preventative measure: publish a short text summary of each lesson in your LMS or on a shared noticeboard. Three sentences. "Today we introduced loops in Chapter III. The key idea: Swift repeats the body once for every value in a range. Students completed sections 1 to 3."

Managing classroom energy

A classroom full of students drawing flags and buildings gets loud. That's fine. The noise is usually good noise: students showing each other their screens, celebrating when something works, asking each other for help.

When it tips into bad noise:

• Off-task chatter that isn't about the code.
• Frustration and swearing at an iPad.
• One student dominating and drowning out pairs.

The reset move. Stop the class, ask everyone to put the iPads flat on the desk, and do a 60-second demo on the projector. Then release them again. Resetting the energy every 15 to 20 minutes keeps the room productive.

The celebration move. When a student finishes a hard exercise (especially Chapter V Union Jack or Chapter VI Neighbourhood Scene), stop the class and project their work on the screen. Let them explain it. The social reward for finishing is as motivating as the intrinsic reward.

Things that will go wrong

A student accidentally deletes an exercise page

The exercise lives in the subscribed book. Deleting their local copy doesn't delete the original. Tell them to open the Playgrounds app home screen, find Geometry Playground, and re-download it. Their progress on other pages is preserved.

A student writes code that crashes Swift Playgrounds

Rare but it happens. Force-quit the app (swipe up from the bottom, flick Swift Playgrounds off the top). Reopen. The book reopens to the page that was crashing. Tap out of that page into the home view, then back into a different page first, then edit the crash page to remove the offending line.

A student can't find the exercise they were working on

They probably added an extra page and got lost. Tap the page navigator (top toolbar) and scroll through the list. Extra pages are at the end of each chapter.

The iPad runs out of storage

Swift Playgrounds books are small (tens of megabytes), but iPads in shared trolleys accumulate crud. If you get storage errors, delete Photos or unused apps. Geometry Playground itself is not the problem.

A student is visibly frustrated and stuck

Sit next to them. Ask them to read their code out loud to you. Nine times out of ten they'll spot their own error while reading. The tenth time, ask "what do you think this line does?" and let them explain each line. You're rarely the one who fixes the bug; the student is, once they slow down.

Pre-lesson checklist (after the first week)

• Know which chapter and section you're teaching today.
• Know which students were absent last lesson.
• Know the one concept you want every student to leave with.
• Have a 60-second demo ready on the projector.
• Have a back-pocket extension for fast finishers.
• Charged iPads ready for handout.

Ten minutes of prep. Less once it becomes routine.

Links

• Overview for the pitch
• Setup for first-time device setup
• Troubleshooting for specific failures
• Teaching FAQ for questions teachers actually ask
• Assessment Strategies for how to grade the work