7-Day One-Line Sketch
Draw one picture a day with a single continuous line, without lifting your pen. Check in once a day.
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Challenge · Facts & stats · iChallenge network
Daily facts and stats about lines in math, maps and time, plus real challenges to put them to work.
The International Date Line runs mostly through which ocean?
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One ranked attempt per day. Practice as much as you like.
Join one, log your days or post your proof. Finishing earns XP and the Finisher badge.
Draw one picture a day with a single continuous line, without lifting your pen. Check in once a day.
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Photograph three examples each of parallel and perpendicular lines in buildings or objects around you. Post a photo link.
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Draw a timeline of your favorite hobby or skill with at least eight dated milestones. Post a photo link or a short write-up.
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Everyone on this arena gets the same five questions each day, from easy to hard. You get one ranked attempt; practice rounds are unlimited.
100 points per correct answer, up to 50 more for answering quickly, a combo multiplier for answers in a row, and 150 bonus points for a perfect round.
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