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Elementary mathematics

Step 1 covers Grades 1–2. All 14 activities for this grade band are now translated into English, with the same quizzes and best-score tracking as the Korean site. Grades 3–4 are live too →

🔢 Number & operations

🔟

Make Ten

Find the number partner that completes ten.

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✖️

Multiplication Arrays

See why groups × items-per-group gives that answer.

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🔢

Carrying & Borrowing Lab

Represent two-digit numbers as tens and ones blocks, then drag sliders to see exactly when carrying and borrowing kick in.

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🌾

Russian Peasant Multiplication

Try a multiplication method that repeatedly halves one number and doubles the other, without memorizing multiplication tables, and see its connection to binary arithmetic.

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📈 Patterns

🔁

Pattern Finder

Figure out what shape comes next in a repeating pattern.

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📿

Bead Pattern Necklace Lab

Look at the repeating bead pattern, choose the bead that comes next, and complete your own necklace.

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📐 Shape & measurement

🔺

Shape Finder

Count sides and vertices, then identify the shape.

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📦

Solid Shape Families

Explore boxes, cylinders, and spheres in the world around us.

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📏

Comparing Things

Compare length, weight, area, and volume.

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🕐

Clock Reading

Read the short and long hands to tell the time.

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⏰

Minutes Before and After

Move the clock hands with sliders to see what time it'll be after a set number of minutes — and what it was before.

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📏

Measuring Length With a Ruler

Line up the 0 mark on a virtual ruler, read the scale, then try guessing lengths by eye.

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🧱

Block Building Shape Lab

Look at the target shape and build the same shape with blocks. Each time you click a column, one block is added.

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📊 Data

🟢

Sorting Things

The same objects group differently depending on the rule.

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🍎

Picture Graphs

Turn a fruit vote into a picture graph and find the winner.

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