Free rounding games with number lines
Rounding replaces a number with a nearby multiple at a chosen scale. To round 34 to the nearest ten, compare 30 and 40. It is four away from 30 and six away from 40, so 34 rounds to 30. Rounding Workshop shows those distances on a number line and lets you explore what changes when the number moves.
Nearest 10, 100 and 1,000
Choose nearest 10 with numbers from 0 to 100, nearest 10 from 0 to 1,000, nearest 100 from 0 to 1,000, or nearest 1,000 from 0 to 10,000. The interval between the two endpoints is one rounding unit. Each drawn interval has ten equal spaces: one, ten or one hundred per space, depending on that unit. The scale is written under every diagram.
The question’s number can sit between ticks when the scale is finer than the labelled spaces. The marker uses its actual position, not a snapped tick. For example, 249 is just below the halfway point of the interval from 200 to 300. It is 49 from 200 and 51 from 300, so it rounds to 200.
Halfway and exact multiples
For the non-negative whole numbers in this game, an exact halfway case rounds to the higher multiple. To round 35 to the nearest ten, 30 and 40 are equally far away, so choose 40. To round 250 to the nearest hundred, choose 300. An exact multiple stays itself: 40 to the nearest ten is 40, and zero stays zero.
The top boundary is included. For 1,000 to the nearest hundred, the line shows 900 to 1,000 and the correct rounded number is 1,000. The game does not extend a route beyond its stated maximum. These activities cover whole numbers only; they do not teach rounding decimals, negative numbers, significant figures or every possible rounding convention.
Explore how rounding changes
Choose a scale, then Explore a number line. Enter a whole number within that scale and choose Show interval. One less and One more move by one without requiring a drag gesture. Show halfway places the number at the midpoint of the current interval. Compare the distances below the diagram and see how moving across halfway changes the rounded number.
Explore does not replace any saved practice or award a sticker. Its current number is temporary; reloading the page starts Explore at 34. The chosen scale is in the link, so you can share a particular kind of exploration without sharing personal progress.
Eight saved practice routes
Each of the four scales has With a number line and Without a number line practice. Both offer two neighbouring multiples as answer choices. The second mode hides the diagram, rather than testing free-form recall. Show working reveals the diagram and answer in either mode; help is available without a penalty.
Each route has twelve distinct shuffled facts: zero, the scale’s maximum, two other exact multiples, two halfway cases, three below halfway and three above halfway. There is no timer or limit on attempts. Choose a multiple and Check my answer. The correct answer stays visible until you choose Next fact; after the last one, choose Finish this route.
The eight routes save independently in this browser on this device, including fact order, current selection, checked state and help use. Reopen the same scale and support choice, then Continue practice. A new browser or cleared storage starts fresh. If saving fails, an on-screen message explains that leaving or refreshing may lose work.
Starting an unfinished route again asks before replacing it. Other routes and earned stickers stay. Completing a route awards its sticker in the sticker book and reports how many facts used the working. These stickers celebrate completed practice, including practice with help; they do not certify independent mastery. Round and sticker saving are checked separately. If sticker saving cannot be confirmed, completion asks you to check the book. Shuffling a completed route gives a new selection that can include familiar facts.
Phone, tablet and keyboard controls
Tap the large answer buttons; the number line is a diagram, so you do not need to hit a tiny point. Use Tab to reach controls and Enter or Space to activate a button. Enter a whole number with the numeric keypad in Explore, then press Enter or Show interval. Holding an activation key cannot repeatedly advance practice facts. Sound does not start automatically.
Explore positions and equal steps in Number Line Workshop, or build and exchange hundreds, tens and ones in Place Value Workshop. For a different addition strategy, try Doubles Workshop.