The post Stairway to the Moon appeared first on Bedtime Math.

]]>Our Moon is bigger than you think. It may look small, but it’s about 2,000 miles across, the same width as the US from Florida to California! The Moon looks teeny only because it’s a quarter million miles away. So our fan Quinn F. asked, how many stairs would you need to walk to the Moon? Well, you’re climbing 240,000 miles, which is more than 1 billion feet (1,267,200,000 feet), or about 15 billion inches. House stairs are supposed to be 7 3/4 inches tall at most. So you need 1,962,116,129 steps — almost 2 billion stairs to climb that high! The problem is, stairs are also 10 inches from front to back. So those stairs would start 310,000 miles way over to the side. You’d have to fly into outer space just to start climbing!

*Wee ones:* Look out the window. Do you see any space objects right now, like the Moon, Sun, or stars? What shapes do you see?

*Little kids:* If you climb steps 2 at a time, after the 2^{nd}, 4^{th} and 6^{th} which step do you touch next? *Bonus:* Once you’ve jumped to the 10^{th} step, how many have you touched in total?

*Big kids:* Can you “spell” 2 billion as a number, without looking at the numbers above? *Bonus:* If you can climb 100 steps in a minute, how many minutes would it take to climb the 2 billion steps to the Moon?

*The sky’s the limit (for real):* While the Moon is 1/4 million miles away, the Sun is 93 million miles away. If you need 2 billion steps to reach the Moon, how many do you need to reach the Sun? (Hint if needed: How many do you need to climb 1 million miles?)

__Answers:__

*Wee ones:* The Sun always looks like a circle; the Moon can be a circle, a gibbous shape (circle with one edge shaved off), a half circle, or a crescent (C shape); stars look like tiny circles.

*Little kids:* The 8^{th} step. *Bonus:* 5 steps.

*Big kids:* 2,000,000,000. *Bonus:* 20 million minutes, which is 13,889 days, or 38 years!

*The sky’s the limit (for real):* 744 billion steps. You need 8 billion steps for each million miles, then need 93 times that number to reach the Sun.

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]]>The post Growing the Great Pumpkin appeared first on Bedtime Math.

]]>With Halloween coming soon, people are gathering pumpkins to carve, paint, or bake into pies. And as shared by our fan Lillian I., for some people no pumpkin is too big. In this video, pumpkin ninja Ron Wallace tells us how he grows his giant pumpkins. In 2009 he was the first grower ever to grow a 2,000-pound pumpkin. Then last year, the 2,230-pounder he grew broke the North American record for the heaviest pumpkin ever – it weighed as much as a small car! Ron works hard to grow these crazy squashes. He replants seeds from other giant pumpkins, spends hours watering and trimming, and chases away mice and bugs. Big pumpkins taste really gross and can’t be baked into pie, but people pay $1,000 just to buy a seed from his farm!

*Wee ones:* Ron has grown 18-foot tall sunflowers. That’s as tall as a stack of 3 grown-ups! Look at a grown-up, and imagine stacking 2 more grown-ups that size on top of his/her head.

*Little kids:* Pumpkins are round. Can you name 3 shapes that are round? *Bonus:* If Ron plants seeds in May and picks the pumpkins 5 months later, in what month does he pick them?

*Big kids:* If you have $800, how much more money do you need to buy a $1,000 magic pumpkin seed from Ron? *Bonus:* If every pound of pumpkin can make 2 pies, how many yucky-tasting pies could be baked from Ron’s 2,230-pound pumpkin?

__Answers:__

*Wee ones:* Picture 3 grown-ups standing on each other’s heads!

*Little kids:* Answers might include a circle, oval, “sphere” (ball) and “torus” (donut). *Bonus:* In October.

*Big kids:* $200 more. *Bonus:* 4,460 pies!

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]]>The post Life-Size Candy Land appeared first on Bedtime Math.

]]>In Candy Land, anyone can win at any time. As you move your little person through the path, you might* **think* you’re about to win as you get near the end. But if you draw a card for a candy near the beginning, suddenly you’re sent all the way back. What if you got to walk up and down a real, life-sized path like that? Some people actually did! When the game Candy Land turned 60 years old in 2009, people made a giant Candy Land board on San Francisco’s Lombard Street, also known as “the crooked street.” Groups of kids dressed in their team’s colors ran down the street when it was their move. We hope they ate some giant candy along the way, too.

*Wee ones:* If the squares in Candy Land are red, purple, yellow, blue, orange, and green, how many colors do they use?

*Little kids:* If you move 2 squares ahead on your first turn, then 5 squares ahead on your next, how many squares do you move in total? *Bonus:* If 3 teams of 10 kids play on this giant board, how would you count up those kids by 10s?

*Big kids:* If Candy Land was 60 years old in August 2009, how old is Candy Land today in 2018? *Bonus:* If the section of street used was 600 feet long and each square was 20 feet long, how many squares long was the path? (Hint: To divide by 20, you’re dividing by 2, then by 10).

*The sky’s the limit:* The colored squares in Candy Land are in the order red, purple, yellow, blue, orange, green (6 colors). If the board starts on red and repeats this order, what color is the 59th square? (Assume there are no candy spaces in the way.) What do you think could be the fastest way to figure this out?

__Answers:__

*Wee ones:* 6 colors.

*Little kids:* 7 squares. *Bonus:* 10, 20, 30.

*Big kids:* 69 years old. *Bonus:* 30 squares.

*The sky’s the limit:* The 59th square is orange, because 60 is a full set of 6, and therefore the 60^{th }square, which follows the 59^{th}, is green.

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]]>The post The Wild Side of Watermelon appeared first on Bedtime Math.

]]>When food shows up in a crazy shape, will it still taste good? You might worry a little when someone hands you a square watermelon. Someone figured out that if you build a plastic box around a growing watermelon, it will grow to fill the corners, and turn into a box shape itself. While these cubic fruits look fun, the price isn’t: 1 cube watermelon can sell for more than $75! Luckily you can grow your own (find out here how to do it). One good thing about this shape is that you can grow 4 times as many cube watermelons as round watermelons inside the same garden space. If they taste good, that’s a great deal.

*Wee ones:* These cube watermelons are shaped like boxes. See if you can spot a box or box shape in your room.

*Little kids:* How many “faces” (flat sides) does a cube watermelon or any box shape have? *Bonus: *How many corners (pointy parts where 3 faces meet) does a cube watermelon have? See if you can find and count them all!

*Big kids:* You can fit 4 times as many cube watermelons as round watermelons in the same garden space. If you can grow 5 round watermelons in your garden, how many cube watermelons could you plant instead? *Bonus:* If you put 12 cube watermelons in 3 rows of 4 to make a rectangle, how many watermelons are in the middle/not on the edge?

__Answers:__

*Wee ones:* Answers might include shoeboxes, or box shapes like building blocks or Lego pieces.

*Little kids:* 6 faces. *Bonus:* 8 corners.

*Big kids:* 20 cube watermelons. *Bonus:* The 2 melons in the middle.

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]]>The post Big Foot – for Real appeared first on Bedtime Math.

]]>That pair of feet looks HUGE, doesn’t it? It’s not just because the person taking the picture snuck up close. Jeison Hernandez has the world’s biggest feet. At almost 16 inches long, they’re longer than a real 12-inch “foot”! Of course, taller people have longer feet, and Jeison himself stands over 7 feet tall. Even so, his size 26 feet still shock and amaze everyone who sees them. In the whole history of the world, the biggest feet ever were bigger than that. Back in the 1930s, the world’s tallest man, Robert Wadlow, had feet 18 1/2 inches long, and wore a size 37AA shoe. All we can say is, don’t try to play soccer against these guys.

*Wee ones:* Stand next to a grown-up so your feet are side by side. Whose feet are longer?

*Little kids:* Hold your right foot against your left forearm (the part from your elbow to your wrist). Which one is longer? *Bonus:* How much taller would you need to grow to stand 7 feet tall like Jeison? Find out your height rounded to the closest foot!

*Big kids:* If Jason wears a size 26 shoe, how many sizes bigger were Robert’s size 37 feet? *Bonus:*For grown-ups, a jump of 3 shoe sizes equals 1 inch in shoe length. If Jason is size 26 and your feet were 6 inches shorter, what shoe size would you wear?

__Answers:__

*Wee ones:* The grown-up’s feet are probably longer!

*Little kids:* Cool fact: on most people, the foot and forearm are close to or exactly the same length! *Bonus:* Different for everyone…find out your height in feet, then subtract from 7.

*Big kids:* 11 sizes bigger. *Bonus:* Size 8, since your feet would be 18 shoe sizes shorter.

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]]>The post Pancakes for Your Pets appeared first on Bedtime Math.

]]>We people love pancakes. It turns out some tortoises do, too. They’re the round-shelled reptile stars of this video. While turtles live in water, their cousin the tortoise likes to eat grass, fruits and veggies. But when handed a stack of tiny little pancakes, these tortoises see that maybe life has yummier food choices. The big tortoise dives right in and munches away, but the little tortoise — who is shorter than his stack of pancakes — isn’t so sure. How would you feel if you were served a stack of pancakes that’s taller than you? Actually, you might dive right in, too.

*Wee ones:* What shape do you think these tiny tortoise pancakes are?

*Little kids:* If the big tortoise has 3 pancakes and the teeny tortoise has 3 of his own, how many do they have together? *Bonus:* If the big guy eats all 3 pancakes and the little tortoise ends up eating 1, how many pancakes are left for you?

*Big kids:* If you can stack 10 people pancakes in a foot, how many pancakes would make a stack as tall as you? You can round your height to the nearest foot or half-foot for this one! *Bonus:* If you’re handed a stack of 60 pancakes and are hungry enough for only 1/4 of them, how many do you eat?

*The sky’s the limit:* If a group of 4 big tortoises and 2 tiny tortoises eats 30 pancakes in total, and each big tortoise eats twice as many as each tiny tortoise, how much does each size tortoise eat?

__Answers:__

*Wee ones:* A circle. Their 3D shape is actually a very short, wide cylinder.

*Little kids:* 6 pancakes. *Bonus:* 2 pancakes.

*Big kids:* Different for everyone…round off your height, and add up 10 for every foot of height and another 5 pancakes for a half-foot. *Bonus:* 15 of them.

*The sky’s the limit:* Each tiny tortoise eats 3 pancakes, and each big tortoise eats 6 pancakes. Since each big tortoise eats double a tiny tortoise, together 2 big tortoises eat 4 times as much as each tiny tortoise, and thus, 4 big ones together also eat 4 times as much as 2 tiny tortoises. That means the tiny tortoises’ set plus 4 more of these sets makes 5 sets of pancakes, which means the pair of tinies eats 6 pancakes. So each tiny tortoise eats 3, and each big one eats double that, which is 6 apiece.

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]]>The post Backyard Ninja appeared first on Bedtime Math.

]]>Have you ever wanted to be a ninja? Ninja were secret warriors in Japan hundreds of years ago (and maybe even today — it’s a secret). A ninja has to leap, run and climb super-fast and super-quietly. Well, one girl decided she wanted to practice to become a ninja. So her very cool dad built her a giant ninja training course in their backyard. As this video shows, she has to jump through a set of slanted boards, balance on wobbly, seesawing beams, and dash over the roofs of not one but two sheds. She finishes the course in about 2 1/2 minutes. Do you think you could do it faster? If yes, you might be a ninja, too!

*Wee ones:* If you leap onto a slanted step facing left, then another facing right, then another facing left, then facing right…which way does the next one face?

*Little kids:* If you’re 10 seconds from finishing the ninja course, what numbers do you say to count down? *Bonus:* If there were 9 slanted steps for her to zigzag through, starting facing left, then right, then left and so on, how many slants would face each way?

*Big kids:* If the whole thing takes 2 1/2 minutes, how many seconds does it show on the stopwatch when she’s done? *Bonus:* If the sheds took a whole 1/3 of that time, how many seconds would they take? (Hint if needed: What if they took just 1/3 of 15 seconds?)

__Answers:__

*Wee ones:* It faces left.

*Little kids:* 10, 9, 8, 7, 6, 5, 4, 3 ,2, 1. *Bonus:* 5 would face left, and 4 would face right.

*Big kids:* 150 seconds. *Bonus:* 50 seconds.

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]]>The post From Dinosaur to French Fry appeared first on Bedtime Math.

]]>When you think of a potato, you probably picture a brown, boring lump. But not all potatoes look like that. Just ask our fans Parker and Kenley M. Their family farm grows thousands of potatoes, and as you see here, some of those lumps grow into really great shapes like hearts, hands, ducks and dinosaurs. Since the kids see potatoes all day and night, they asked us, how many potatoes would it take to feed the world? Well, mashed potato recipes tell us to cook 1/2 pound of potato per person, which works out to be 1 potato each. So 8 billion people need 8 billion potatoes for that one meal. Turns out that we each eat about 69 *pounds* of potatoes each year…the question is, how many of those look like ducks?

*Wee ones:* When you slice through a normal-shaped potato (or look at it from the end), what shape do you see?

*Little kids:* Potatoes can be brown, red, or golden. If you have 2 potatoes of each color, how many potatoes do you have? *Bonus:* If 2 of those potatoes are dinosaur-shaped, how many aren’t?

*Big kids:* If a regular potato weighs 1/2 pound, a duck-shaped potato weighs twice as much, and a dinosaur-shaped potato weighs twice as much as the duck, what do all 3 weigh together? *Bonus: *If you eat 2 potatoes each week, and every 6th potato starting with the 6th is duck-shaped, in what week will you eat your 3rd duck?

*The sky’s the limit:* If each of the world’s 8 billion people eats 69 pounds of potatoes this year, how many pounds is that – and how many potatoes? (Trick for multiplying: 8 is 2 x 2 x 2, so you can just double the number 3 times! Another trick: what if it were 70 pounds a year, and how different would that be?)

__Answers:__

*Wee ones:* A circle.

*Little kids:* 6 potatoes. *Bonus:* 4 potatoes.

*Big kids:* 3 1/2 pounds. *Bonus:* The 9th week.

*The sky’s the limit:* 552 billion pounds. That’s 8 (billion) less than 560 (billion) pounds, which would be 70 pounds per person.

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]]>The post Give Me a High Five — or Fifty appeared first on Bedtime Math.

]]>It’s a lot easier to have legs in pairs. That way you won’t fall over when you walk. We humans have 2 legs, and so do all birds. Mammals like bears and bunnies have 4 legs. All bugs have 6 legs. Spiders and octopus have 8. The one odd man out is the starfish. Most of these prickly, scratchy ocean friends have 5 legs. But there are over 1,800 types of starfish, or “species,” and they don’t have to have just 5 legs — they can have up to 50! Even with all those legs, if a starfish loses one, it can just grow a new leg through regeneration. When you start with 40 or 50 legs, do you even care if you’re missing one? But it looks like these guys keep count.

*Wee ones:* Hold up 5 fingers to pretend your hand is a starfish!

*Little kids:* If you have a 5-legged starfish, a 12-legged starfish, and an 8-legged starfish, which one has the most legs? *Bonus:* Which 2 starfish have 13 legs together?

*Big kids:* If you have a pile of pet starfish with either 5 or 8 legs, how many of each type must you have if they have 26 legs all together? *Bonus:* If you stick 50 pet starfish on your 4 bedroom walls to decorate, can you put the same number of stars on every wall? If not, how many leftover starfish do you have? (Assume each star touches only 1 wall.)

__Answers:__

*Wee ones:* See if you can hold up 5 fingers!

*Little kids:* The 12-legged starfish. *Bonus:* The 5-legged star and the 8-legged star.

*Big kids:* Two of the 5-legged ones (10 legs between them) and two of the 8-legged ones (16 legs between them). *Bonus:* Not quite – you’ll have 12 on each wall, with 2 starfish left over.

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]]>The post It’s Inktober! appeared first on Bedtime Math.

]]>Our longtime fan Ajax L. just told us that October is also Inktober (and sent us his own cool ink drawing of dragons and Minecraft Creeper!). The challenge is to draw an ink drawing every day this month. People all over the world are drawing ink pictures, and taking photos of them to share with others. Drawing in ink isn’t new: the oldest cave paintings were drawn over 40,000 years ago, using everything from vegetable juices to tree sap to crushed rock. Only about 5,000 years ago did people start using ink to write; before then, they used ink only to draw people, animals, and the natural world. The ink you find in your pens today isn’t too different from paint. It’s a mix of chemicals with dye added to make different colors. Since it’s Inktober, try drawing with as many as you can!

*Wee ones:* When you draw with a pen, what’s your favorite color to use? See if you can spot 4 things in your room in that color.

*Little kids:* If you draw a crazy zebra with a blue stripe, then a black stripe, then a red one, then blue to start over, what 3 stripes come after that blue one? *Bonus:* How many more stripes do you need after all those to have 10 in total?

*Big kids:* If cavemen started drawing 40,000 years ago and writing 5,000 years ago, for how many years did they just draw? *Bonus:* If instead of drawing daily, every 3 days starting Oct. 3 you draw 4 ink drawings at once, how many will you draw in Inktober?

*The sky’s the limit:* If you draw a picture every 5^{th} day starting on a Monday, will you ever draw on a Wednesday? Why or why not?

__Answers:__

*Wee ones:* Different for everyone…find 4 things in your favorite ink color.

*Little kids:* Black, then red, then blue again. *Bonus:* 3 more stripes, since you have 7 already.

*Big kids:* 35,000 years. *Bonus:* 40 pictures, since you’ll draw 10 sets ending on Oct. 30.

*The sky’s the limit:* Yes. You’ll draw on Mon, then Sat, Thurs, Tues, Sun, Fri, Weds, and back to Mon. In fact, you’ll draw at some point on every day of the week. Because 7 isn’t divisible by any numbers other than 7, *any* number that isn’t 7 or a multiple of it will cycle you onto every weekday.

The post It’s Inktober! appeared first on Bedtime Math.

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