🔢 Jack's Numbers

Count, add and subtract with footballs — to 10, then to 20

What this is

An early-years maths game — counting, addition and subtraction, first to 10 and then to 20. Every sum is shown as countable objects before it is shown as arithmetic: the footballs are there to be tapped one at a time, and each tap counts out loud and marks the ball with its number. The abstract sum sits above them; the concrete quantity sits underneath.

Above ten, the balls are laid out five to a row with a break after the tenth — the ten-frame representation used in Year 1 classrooms, which makes bridging ten something a child can see rather than something they have to calculate.

🎮 How to play

1️⃣   Look at the footballs ⚽⚽⚽

The sum is made of real objects.

2️⃣   Touch them to count 👆

Each tap says one, two, three… and numbers the ball. Reaching the end clears the marks so the same set can be counted again.

3️⃣   Pick the answer 🟨🟩🟦🟪

Four coloured tiles, one of them right.

⚽   GOAL!

A correct tile wins a football. A wrong one wobbles and the question is repeated — nothing is lost and there is no timer.

📈 It grows with the child

🐣 To 10	counting 1–10, addition and subtraction within 10
🚀 To 20	switched on with ⚙ — counting to 20, addition bridging ten (8 + 8, 9 + 7), subtraction inside twenty (17 − 5)

Turning the bigger range on adds levels after the existing ones rather than replacing them, so nothing a child has already mastered suddenly gets harder.

⚽⚽⚽⚽⚽      twelve reads as
⚽⚽⚽⚽⚽      ten and two,
              not as a heap
⚽⚽

🎯 What it practises

• 🔢   One-to-one counting of visible objects
• ➕   Addition across the ten boundary
• ➖   Subtraction within twenty
• 🧠   Reading a quantity from a ten frame at a glance

🎈 The other games

Game	What it is
🔟 Jack's Ten Frames	See numbers in fives, make ten, then add past ten on ten frames	▶ play
⏰ Jack's Clock	Read the clock and set the hands — o'clock, half past, quarter past, quarter to	▶ play
💯 Jack's Big Numbers	Tens and ones, adding and taking away all the way to 100	▶ play
👀 Jack's Sight Words	The twenty most common English words on big cards — tap one and hear it read out	▶ play
🍎 Jack's Apples	Trace 1–20, then fill the missing numbers into the apple grid	▶ play
🥅 Jack's Match	Tell real words from decodable nonsense words, then spell by ear	▶ play
✏️ Jack's Letters	Finger-trace all 26 lowercase letters in the correct stroke order	▶ play
🔢 Jack's Numbers	Count, add and subtract with footballs — to 10, then to 20	▶ play 👈 this one
📖 Jack's Words	Hear a word, build it from letter tiles, then read it in a sentence	▶ play
♟️ Jackies Schach	Full FIDE rules with a coach that marks the safe squares (German)	▶ play

All ten on one start page: jackbenn.ing — newest first, homework on top, chess always last.

🛠 Built like this

Every game in this organisation is one self-contained index.html — no build step, no framework, no package manager, no analytics, and no network calls beyond its own voice clips (chess also loads its rules engine, chess.js, from jsDelivr, and Sight Words its font from Google Fonts). That is a deliberate constraint: a game a child depends on should still work in five years, and a parent should be able to read the whole thing in one sitting.

• Speech — pre-rendered clips of the neural en-GB-SoniaNeural voice, played through Web Audio, with the Web Speech API as the fallback. The AudioContext is created inside the ▶ tap, because iOS refuses to start audio any other way.
• Progress — kept in localStorage on the device. Nothing is collected, sent or stored anywhere else.
• Made for an iPad mini in either orientation: finger-sized targets, no hover-only interactions, prefers-reduced-motion respected.

Run it locally:

python3 -m http.server 8000

The start page at jackbenn.ing is built from google814/Jack, which is the source of truth. The repos in this organisation are copies kept in step by tools/sync-game-repos.sh in that repo, so each game also has its own page and its own link.