The post Wrong Kind of Balloon Ride appeared first on Bedtime Math.

]]>For some people, flying 35,000 feet above the ocean on a plane isn’t exciting enough. They have to strap themselves to a bunch of balloons and float across. That’s exactly what Jonathan Trappe set out to do a couple of years ago, when he climbed into a basket tied to 370 helium balloons and took off. He started in Maine and hoped to cross the Atlantic Ocean. Had he succeeded, he would have been the first person ever to do it with helium balloons. Well, his trip ended just 12 hours later, when his balloon started having problems and he had to land in Newfoundland (part of Canada). To this day no one has made it across the ocean this way. So if you can track down hundreds of party balloons, you can try to be first!

*Wee ones:* Jonathan’s balloon went up, then down. Look straight up — what do you see? Now look down — what do you see this time?

*Little kids:* Which color balloon shows up the most, and how many of them can you see at least partly? *Bonus:* If that was out of 20 balloons total, would there be more yellow balloons or non-yellow balloons?

*Big kids:* Trappe was 39 years old when he tried this 5 years ago. If he tries again 10 years from now, how old will he be? *Bonus:* If each of those 370 balloons can hold up 1 pound, and Trappe weighed 180 pounds, how many pounds could his basket, snacks, etc. weigh all together?

__Answers:__

*Wee ones:* Looking up, you might see the ceiling, or the sky! Looking down, you might see carpet, floor, dirt or grass — and your feet.

*Little kids:* 7 yellow balloons: 3 in the upper left, 1 in the middle, and 3 on the right, by our count. *Bonus:* There will be more non-yellow balloons, since half would be 10.

*Big kids:* 54 years old, since he’s now 44. *Bonus:* 190 pounds.

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]]>The post The Tortoise That (Almost) Beats the Hare appeared first on Bedtime Math.

]]>When you think of a speedy animal, we bet you don’t think of turtles or tortoises. After all, the tortoise was the slow guy in that story with the hare. But some tortoise out there has to be the fastest one. Last fall, Bertie broke the world record for a tortoise “running” on a track. He crawled almost 18 feet in less than 20 seconds. That’s about 2/3 of a mile per hour…just to compare, we people *walk* about 3 miles an hour. He was more than twice as fast as the previous record, set in 1977 by a tortoise named Charlie. That said, no matter how you do the math, Bertie can’t beat a speedy rabbit — unless that rabbit really screws up.

*Wee ones:* Walk across your room. Now run back across your room. Which way were you faster?

*Little kids:* Bertie “runs” about 1 foot each second. How many feet does he run in 5 seconds? *Bonus:* Who’s faster, a tortoise at 90 feet per second or a rabbit at 900 feet per second?

*Big kids:* If Bertie could run 18 feet in 20 seconds, how far could he run in 40 seconds at the same speed? *Bonus:* Bertie takes 1 hour to run 2/3 of a mile. How fast can a rabbit running 60 miles an hour run it? (Hint: How far does that rabbit run in 1 minute?)

__Answers:__

*Wee ones:* You were faster when you ran!

*Little kids:* 5 feet. *Bonus:* The rabbit is faster.

*Big kids:* 36 feet, since he has twice as much time. *Bonus:* In 2/3 of a minute, or 40 seconds!

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]]>The post How Do Doggie Treats Taste? appeared first on Bedtime Math.

]]>Dogs love their doggie treats. That’s why we use them to teach dogs new tricks. But did you ever wonder what’s in a doggie treat, or whether it tastes good? Dog biscuits are made of flour, egg and milk, which sounds yummy…but then they’re flavored to taste like meat or fish, which doesn’t sound so yummy*. Someone* must think they taste good, though, because 10 bakers at a pet-food company in Missouri decided to bake the biggest doggie treat ever. The previous record, baked in England, had weighed a jaw-dropping 231 pounds. But these new people baked a biscuit that weighed 617 pounds. Hopefully someone gave them a nice big treat for that.

*Wee ones:* If you mix corn flour, milk, egg, ground chicken, and fish juice to make doggie biscuits, how many foods did you use?

*Little kids:* If your dog gets 2 treats every day for doing tricks, how many treats does she get in in a stretch of 5 days? Try to count up by 2s! *Bonus:* If you give your dog 1 treat for every trick, but 3 treats instead for every 3^{rd} trick (starting on the 3^{rd}), how many treats does she get for 6 tricks?

*Big kids:* If you and your dog start eating doggie treats on a Tuesday, and he eats 4 per day while you eat 2 per day, on what day do you guys finish a 20-treat box? *Bonus:* How many more treats than you will your dog eat in a 31-day month?

*The sky’s the limit:* If you’re baking 36 treats and all the neighborhood dogs smell them and come running, how many dogs could show up such that you could split the treats equally among them? (You can count just the visiting dogs, not your own dog…but at least 2 dogs show up.)

__Answers:__

*Wee ones:* 5 foods.

*Little kids:* 10 treats. *Bonus:* 10 treats again.

*Big kids:* On Friday, since by end of Thursday you’ve eaten 18 in total. *Bonus:* 62 more, since the dog eats 2 extra each day.

*The sky’s the limit:* You could have: 2 dogs, 3, 4, 6, 9, 12, 18, or 36 dogs and divide up the treats equally.

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]]>The post Triple-Trick Dominoes appeared first on Bedtime Math.

]]>Domino chains are so simple but so cool. You stand them up on end, then knock down just the first domino. It knocks over the next one, which knocks down the next, until the ripple runs right through. But one little row is nothing compared to this mindblowing video of a “triple spiral” domino chain! Domino pro Lily Hevesh builds giant domino designs, full of stacked layers, staircases and lot of colors. In this one, one lower level spirals inward, then sets off another lower level going outward. Finally it takes down the skinny 3-story walls. We love how the tippy-top dominoes start it off without breaking anything under them. It took Lily 25 hours and about 15,000 dominoes to build this. It’s hard work: one wrong move, and they all fall!

*Wee ones:* What shape is a domino?

*Little kids:* The spiral going in uses red, orange and yellow dominoes, and the one coming out uses light blue, medium blue and dark blue. Which spiral uses more colors? *Bonus:* Those spirals have 9 rows of dominoes. Which row is the exact middle one?

*Big kids:* If Lily worked on this 8 hours a day starting on a Tuesday, could she have finished in time to post on Saturday? *Bonus:* If 1/3 of the 15,000 dominoes are in the cool triple walls, how many dominoes is that?

__Answers:__

*Wee ones:* A rectangle (or in grown-up 3D lingo, a “rectangular prism”).

*Little kids:* They use the same number! 3 colors each. *Bonus:* The 5^{th} row.

*Big kids:* Yes: she would have just one last hour on Friday. *Bonus:* 5,000 dominoes.

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]]>The post Sizing It Up appeared first on Bedtime Math.

]]>The biggest cookie. The longest pretzel. The largest balloon. When it comes to kids and treats, bigger is always better! What we might not notice is that all those crafty calculations involve mental math. At a young age, our children are learning to compare and estimate length, width, weight and other quantities to pick the best choice.

Why do these skills matter? One informal study found that kindergartners’ ability to estimate on the fly the number of objects in a pile– called “subitizing” – was an almost perfect predictor of kids’ success or struggles with math in first grade. Those who could look at up to 5 objects and guess the total quickly and correctly emerged as the better math students a year later.

Guess what: kids build these skills in real life, not just at school. In fact, kids spend only about 1/4 of their waking hours at school over the year! If children can gain a leg up by building number and spatial sense during play, let’s make that happen. Here are 3 fun ways to mix in math at home!

#1. **Line ‘Em Up**

That pencil line-up is an easy activity that can be done with other objects, too, and the results have a zen regularity. Find 8-10 objects of a set and line them up from shortest to longest, or vice-versa. Notice that your line-up looks like a bar graph – great pre-training for algebra!

#2. **Stack Attack**

Just as we can compare the sizes of objects like pencils, we can compare piles of multiple items. Which color crayon shows up the most? Which color M&M? Make a nice straight line for each set, and see how again you produce a cute little bar graph.

#3. **Too Big? Too Small? Just Right!**

Goldilocks and the Three Bears teach a great lesson on moderation: sometimes the middle one is the best, not the biggest or smallest. As a bite-sized ramp-up, ask kids to find 3 similar objects – 3 circles, 3 furry things, 3 things we’d love to wear on our head – and place them in a row in size order. Size can increase from left to right or right to left, helping reinforce this spatial skill at the same time. See how many items you can add to the mix!

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]]>The post Trip to the Sun appeared first on Bedtime Math.

]]>Our question this weekend about the weight of the Sun got a lot of kids thinking. Our fan Dillon M. then asked, how do we measure the distance from the Earth to the Sun? Well, there are a couple of ways to do it. Back in ancient Greece, Aristarchus figured it out by waiting for a half-moon, then looking at the angle of light from the Sun hitting the Earth and making a triangle. But now that we know how big and how far the Moon is, we have an easier way. Ever notice how the Sun and Moon look the same size in the sky? That’s because the Sun is 400 times as wide – nearly 800,000 miles compared to 2,000 —* **and* it’s about 400 times as far. The Moon is 240,000 miles away, so that would give us 96 million miles for the Sun. That’s not too far off from the answer, but too far to go there for the day!

*Wee ones:* The Sun is much bigger than Earth, which is bigger than the Moon. Find 3 objects and put them in a row from biggest to smallest.

*Little kids:* Turn on a light, and hold a pencil sticking straight up from a table. Is its shadow longer or shorter than the pencil? *Bonus:* If the pencil is 5 inches tall and its shadow is twice as long, how long is the shadow?

*Big kids:* The Moon takes about 15 days to go from half-moon facing right (a “D”) to half-moon facing left (a “C”). If the D happens on Tuesday, what day will the next half-moon be? *Bonus:* The Moon actually takes 29 days to go all the way around once. How long is exactly half of that?

*The sky’s the limit — literally:* If the Sun were exactly 100,000,000 (100 million) miles away and you could fly 25,000 miles each day, how soon could you get there? (*Hint if needed:* How long would it take to fly 100,000 miles?)

__Answers:__

*Wee ones:* Items might include a book, a toy, a stuffed animal, or a shoe.

*Little kids:* Different for everyone…the lower/more to the side the light is, the longer the shadow. *Bonus:* 10 inches.

*Big kids:* On a Wednesday. *Bonus:* 14 1/2 days.

*The sky’s the limit:* 4,000 days, which is more than 10 years!

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]]>The post Best Suited for Guinea Pigs appeared first on Bedtime Math.

]]>You might not be a knight in shining armor, but your pet could be. We just love that someone made this suit for his furry pet guinea pig, Lucky. Armor is metal clothing that long-ago soldiers called knights used to wear hundreds of years ago. It kept them safe from enemies swinging swords at them. Metal is stiff and heavy, though, making it hard to move around while wearing it. So the metal had to be linked together in lots of tiny pieces, like chains. That’s why it’s called “chain mail” armor. Who knows why Lucky needs chain mail — when is he going into battle with anyone? But he sure looks handsome. Looks like other guinea pig owners liked it, too: the suit sold online for more than $1,000!

*Wee ones:* If your guinea pig weighs 2 pounds and that little suit of armor weighs 3 pounds, which one weighs *less*?

*Little kids:* If you and Lucky suit up for battle, how many legs do you have together? *Bonus:* If you need to link together 60 loops to make the armor, what numbers do you say to count them off in 10s?

*Big kids:* If your Under Armour underwear costs $100, how many pairs could you buy instead of the $1,000 guinea-pig armor? *Bonus:* If *you* wear real metal armor that weighs 1/2 of what you weigh, and you and the armor weigh 75 pounds, what do you weigh?

__Answers:__

*Wee ones:* The guinea pig weighs less.

*Little kids:* 6 legs. *Bonus:* 10, 20, 30, 40, 50, 60.

*Big kids:* 10 pairs. *Bonus:* You weigh 50, and the suit weighs 25. You’re the same as 2 suits, so the 75 pounds is like 3 suits.

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]]>The post Your House, Made of Lego appeared first on Bedtime Math.

]]>What if you could build your own house out of Lego? How many pieces would you need? Luckily for us, a company made an online calculator to help figure that out. You type in your house size in square-foot area, and the number of floors. The calculator uses math to say how many 8-peg Lego bricks are needed to build that house! How does it do it? We know that a Lego brick is about 1/4 inch thick, 5/8 inch wide, and 1 1/4 in long. Meanwhile, a real clay brick is 2 1/4 x 4 x 8 inches. So you need 359 Lego bricks for each real one. Turns out you need more than 10 million Legos to build your average 2,000-square-foot house. But watch out: that covers only the outside walls. If you want lots of inside walls to make rooms, you’ll need even more Lego!

*Wee ones:* A Lego brick is shaped like a box. How many faces (flat sides) does it have? Find a box and count them up!

*Little kids:* If you start building your bedroom wall with 2 red bricks, 2 yellow, 2 blue, 2 green and 2 white, how many bricks is that? *Bonus:* If you put 2 8-peg Lego bricks next to each other, how many pegs do you have in total – and how many ways can you place the 2 bricks so pegs line up? (Assume they’re the same color.)

*Big kids:* The square foot area of a space is the length times the width. If your bedroom is 10 feet long by 9 feet wide, how many square feet do you have? *Bonus:* If the two long walls in that 10-million brick house each have 1 million more bricks than each of the 2 short walls, how many bricks are in each wall?

*The sky’s the limit:* If your bedroom covers 20 square feet, what are all the combos of lengths and widths that it could be (using only whole numbers) — and which combo would need the most length of wall?

__Answers:__

*Wee ones:* 6 faces – remember to count the top and bottom along with the 4 side faces!

*Little kids:* 10 bricks. *Bonus:* 16 pegs. There are 5 ways to line them up: side by side in a square, end to end in a line, a T (one pointing to middle of the other), and 2 ways to make an L.

*Big kids:* 90 square feet. *Bonus:* 3 million bricks in each long wall, and 2 million in each short wall. Each long and short together use half the bricks – 5 million – and then you need 2 numbers 1 million apart that add to 5 million.

*The sky’s the limit:* 3 combos: 1 foot by 20 feet, 2 by 10, and 4 by 5. The 1 by 20 will need 42 feet of wall (20 + 20+ 1+ 1), while the 4 by 5 needs only 18 feet (5 + 5 + 4 + 4). The proportions of the space makes a huge difference!

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]]>The post When Rubber Duckies Sail the Seas appeared first on Bedtime Math.

]]>Bathtime is always more fun with a rubber duckie. But what would happen if those rubber ducks went out onto the ocean? Well, we found out when a giant load of rubber duckies fell off a ship near Hong Kong in 1992. The toys floated off every which way, and everyone thought they were lost forever. But decades later, the rubber duckies started washing up on beaches all over the world. As the waves pushed the ducks, it showed where ocean currents flow and how fast. The ducks took only 4 years to reach the west coast of the U.S., but about 15 years to reach England. They’ve been nicknamed the Friendly Floatees by scientists watching their path. We hope the people who catch a duckie bring it home for a nice warm bath.

*Wee ones:* Rubber duckies are usually yellow. See if you can find 4 yellow things in the room.

*Little kids:* If 5 ocean-floating rubber duckies bump into 1 more friend, how many duckies does the group have now? *Bonus:* If starting now some of the duckies float for 3 years before reaching a beach, how old will you be when they arrive?

*Big kids:* If 2 ducks, Squirty and Squeakles, start 500 miles apart, and each one floats 300 miles from their starting point, could they meet up? *Bonus:* If 28 rubber duckies start floating from Hong Kong, half of them make it to California, and then half of *those* make it to Mexico, how many duckies make it to Mexico?

__Answers:__

*Wee ones:* Items might include clothes, socks, pillows, or a picture on the wall.

*Little kids:* 6 rubber duckies. *Bonus:* Different for everyone…add 3 to your age today!

*Big kids:* Yes! Because if they swim straight at each other, they each need to travel only 250 miles. *Bonus:* 7 rubber duckies, since 14 make it to California.

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]]>The post A McNugget That Made History appeared first on Bedtime Math.

]]>Chicken McNuggets aren’t anything fancy. They’re just food (well, sort of: chicken plus lots of salt and fat). But one McNugget became very famous for its looks. Rebekah Speights was eating at a McDonald’s in Nebraska, and found a piece of chicken that looked exactly like George Washington! Can you see his eyes and nose, and the back of his wig? She posted a picture of it on the eBay website, and someone actually paid $8,100 to buy it. Rebekah didn’t keep the money — she gave it to a church in her town, which is nice. What’s funny is that she’d already had the McNugget for 3 years before selling it. We hope whoever bought it didn’t try to eat it.

*Wee ones:* If you’ve eaten 2 McNuggets so far, what numbers do you say for the next 3 that you eat?

*Little kids:* If you’re eating McNuggets and the 2^{nd} looks like a Pokemon character, and so do the 4^{th} and 6^{th}…what’s the next McNugget that looks like a Pokemon? *Bonus:* By the time you’ve eaten 10 McNuggets, how many have you eaten that look like Pokemon characters?

*Big kids:* If the McNugget sold for $8,100 but Rebekah paid $10 for the box of them, how much extra money did she end up with? *Bonus:* If the Washington McNugget sold for $8,100, but a Lincoln one sells for only half, for how much does it sell?

__Answers:__

*Wee ones:* 3, 4, 5.

*Little kids:* The 8th. *Bonus:* 5 McNuggets.

*Big kids:* $8,090. *Bonus:* $4,050.

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