NumberVerse

Numbers are built — place by place, jump by jump. Compose them from base-ten blocks, find where they sit on the line, see quantities in fives and tens, then meet the guides who each teach one piece of number sense.

Level 1

For grown-ups — progress report →A private, on-device snapshot mapped to the skill areas practiced. Export a CSV or print — nothing leaves this device.

Build & reason — hands-on number surfaces

Three ways to feel how numbers work, rebuilt for the browser — the same ideas as the iOS app.

Number Studio Build a number from thousands, hundreds, tens, and ones — watch the standard, expanded, and word forms update, and trade 10-for-1 to regroup. Number Line Place a number, round to the nearest ten or hundred, work with integers and absolute value — and solve by choosing your own jumps. Rekenrek A quick-look bead rack: see a quantity in fives and tens (don’t count!), and build make-ten pairs.

Practice the concepts

12 kits from place value up to integers and absolute value — a short round of questions with a hint whenever you get stuck. Your progress stays on this device.

Play together · new on the web

Number Duel — a head-to-head kit round for 2–4 players. Take turns on one device, or join a friend in an online room by code. Highest first-try score wins; no chat, no accounts.

⚔️ Start a Number Duel →

Mixed practice · new on the web

Shuffles questions across the kits you've learned and brings them back when they're ready to review — a calmer way to keep old skills fresh. On-device only; practice a couple of kits first.

🔀 Start Mixed practice →