2nd Grade Math Compilation

number times zero, you will always get zero. you always get zero here is an example five times zero equals zero when you have zero groups of five that means you have zero there is none whenever you multiply any number by zero you always get zero one hundred times zero equals zero even if zero is the first number in the equation you always get zero when you multiply by any number, for example, zero times eleven is equal to zero and zero times 1,000 is equal to zero if you multiply any number by zero you always get zero, oh, this has been very funny, here's the next trick if you multiply any number by one it stays the same look at these seven times one equals seven one hundred times one equals one hundred thirty-three times one equals thirty-three if you flip them the answer is still the same one times seven equals seven one times one hundred equals one hundred one times thirty-three equals thirty-three honestly the order of the numbers multiplied does not change the answer.

If you reversed the number of groups and the number in each group, you would still get the same answer, although we recommend this very simple way: the number in each group multiplied by the number of groups to get your The answer is that the two tricks have been: If you multiply any number by zero, you always get zero and if you multiply any number by one, it remains the same. The last multiplication trick is to use multiplication tables, they come in all shapes and sizes but they are all useful especially when you are learning to multiply for the first time here are some examples of multiplication tables there is a table for all the numbers from 1 to 10.

Some children memorize tables like these so that they know immediately in a moment what the answer could be for certain multiplication problems this is how multiplication works the number in each group multiplied by the number of groups gives us our answer oh this one It's such a heavy car oh my god oh it's hard work you know many times learning can It will also be hard work, but we hope these videos are really useful. Make learning fun so learning isn't as hard as pushing this cart. Oh my gosh, okay, what should we learn next? Let's learn about three-dimensional shapes.

This will be. I love 3D shapes A lot of people know about 2D shapes Maybe you don't know about 3D shapes You are in the right place before we start Let me dance here real quick This is really cool music I like it a lot You know? like dancing, you know, some people aren't dancers, you know, I dance, I dabble and I dance, you know, okay, that's enough, can someone please turn off that music? and seriously, I can't, I can't teach like that, I can't teach. With this music playing, you know, I feel like I'm in a candy store, let's turn off the music, please, thank you, so here are our old friends, the 2D shapes, that you're familiar with.

You know you're familiar with the circle. the oval the triangle the pentagon the trapezoid the hexagon the square the rectangle the parallelogram and the octagon and these are not all our shapes our 2d shapes you know, but these are all friends of our family that we do not want to forget these and before looking at the 3D shapes, it's very important for us to look at these shapes again because they're old friends, so we're going to look at each one of them one by one just to make sure you know who they are before you see them. learn all these new shapes this first shape doesn't even need an introduction is the circle the circle that round shape is amazing we love this shape it's one of the first ones we learn the circle the next shape is one of the elastic shapes oval is like a circle stretched is elongated is a tremendous shape the oval here is another familiar shape the three-sided triangle we love the triangle the triangle is great the three-sided friend three sides a triangle wait I keep saying that we love shapes i I mean, we like shapes , but do you love the shapes?

Do I love shaves? I mean, I don't know, I need to take it easy. Okay, let's continue. Ah, the square, the four equal sides. You know the square is good. The square has a good shape. You know, sometimes you just need a square. Sometimes you just need a square. Here is the rectangle. The rectangle is longer than the square because the four sides are not equal. I know the rectangle, I know we are in the middle of something. here but I have to show this okay so what do you call a hamster with a top hat abra hamster lincoln I'm rambling about the trapezoid a cool shape with two of the sides parallel to each other in the parallelogram another four sided shape both pairs of the sides are parallel to each other and finally the pentagon with five sides, the hexagon with six sides and the octagon with eight sides, what amazing shapes, so let's go ahead and do a quick quiz on 2D shapes.

I need your help, I want to see if you really learn these, if you really know them before we get into the 3D form, so help me here, we're going to have a wonderful time wait, what's my birthday? Oh well, the type of shape is at the top, yes, a circle, what type of shape is it? in the middle an amazing square okay now what shape is at the bottom of course a triangle amazing work now we have more this is a little more complicated what shape is in the middle yes a trapezoid whose shape is on the right the pentagon good job and what shape is on the left, yes the square, now try this, what shape is at the bottom, yes the oval, what shape is at the top, yes the parallelogram, what shape is in the middle, very okay, the rectangle, good job, very good, the last one, what shape is on the left, yes, the hexagon, what shape is on the right, gray, the octagon and what shape is in the middle, great, the pentagon, okay, we are ready to learn 3D shapes, we will learn to identify three-dimensional shapes if If you are having trouble completing the quiz, you may want to watch the first part of the video again;

If not, let's get started, so as we get started, it's important to remember what makes a 3D shape a 3D shape. There's an old rhyme that says 3D shapes are fat, no. plane and you can see that with the sphere which is a 3D shape that we are about to learn and the circle the circle is flat but the sphere is 3D it is three dimensional all the shapes are like that so let's learn all these 3D shapes so that The first shape 3D that we are going to learn is the sphere, the one we just mentioned, the sphere is the 3D version of the circle, it is perfectly round, there are spheres around us, one of the spheres that we see all the time are balls like this soccer ball. ball a soccer ball is a sphere it's perfectly round it's a three-dimensional circle it's a sphere you know this sphere yes, it's the earth it's where we live our planet is a sphere how cool is it that our own planet is a perfectly round sphere it's a sphere in In this image we have two spheres, can you see them?

Yes, the two spheres are the two bowling balls. Perfect round spheres. The spheres are around us. Here we have a group of three spheres and you can count them right now. One, two, three spheres, all together, the shape. of a ball, a perfectly round sphere, well there you have it, the sphere, what a cool 3D shape to start with, it's round, there are examples all around us and it's cool, and you know, 3D shapes will get even better in our second 3D. The shape is the cone. The cone has a really cool shape with a circle as the base or bottom and everything comes to a point called the vertex.

Here is an example of a cone. I think we all love the ice cream cone if that's what it is. If you had ice cream inside and you turned it over, you could see the base of the circle and it all comes to a point called the vertex. There are two cones here, a red cone and a blue cone, and you can see both cones. I have that circular base and everything reaches a vertex what wonderful cones have you seen before these are traffic cones here there are many cones, I didn't count them all but there are many and they are wonderful and wonderful cones, so that is our second 3D shape, the cone, a wonderful cone with a great circle base, everything reaches a point called the vertex, how amazing is it that our third 3D shape is the pyramid, I love the pyramid, the pyramid is great, it reaches a point just like the cone Except for the base, it is a square and the sides, instead of being smooth, are triangles.

Okay, these are awesome. The pyramids of Egypt are so cool. You see that they have triangular sides and the bases of these pyramids are square. amazing examples of the pyramid this is a cool pyramid, it is a decoration that connects to the wall, but it is a great example of what a pyramid looks like: the bottom or the base is square and there are triangles on the sides, how cool it is this. another pyramid and it's made of glass there are so many decorations and things around maybe even your house that is shaped like a pyramid because pyramids look so cool people love to put them everywhere and there you go I mean you know, The pyramid has a good shape.

I know you see a lot of them around, they have a square bottom or base and triangles on the sides and everything goes up to a vertex. It is a classic shape. It's pretty impressive. Our fourth 3D shape is the cylinder. Now a cylinder is easy. to detect because it has a circle on the top and a circle on the bottom and it's smooth all around here we have a soup can and it's a cylinder it has a circle on the top a circle on the bottom and it's smooth all around everywhere the cans and most of the jars are cylinders here we have three cylinders are candles and I can tell you a secret most of the candles are cylinders two right, oh my god, this is too crazy and too amazing here are two more cylinders, are you kidding?

Just kidding, even batteries are cylinders, cylinders are everywhere, seriously, a circle on the top, a circle on the bottom and smooth around, I mean, really the cylinder is everywhere, I mean, you know the circle at the top, a circle at the bottom, smooth around, a cylinder like what do you have to be everywhere? The next 3D shape is the cube. The cube is the 3D version of the square. It has six sides or faces that are all square. Here we have two dice. The dice are cube-shaped. so these two dice are two cubes they have six sides or faces that are all square here we have many cubes these are cubes that are made of wood each of them has six sides or faces that are all square here there are seven ice cubes do they have any Have you ever had a hot drink and need to put ice in it?

It's amazing because it has this great shape, the shape of a six-sided cube or facing all squares. I mean, there you have the cube, the 3D version of a square and it has squares along the sides, there are six sides or faces, all squares and I don't know, I think it's a cool shape, our final 3D shape is the prism rectangular, the rectangular prism is the 3D version of the rectangle, it has six sides or faces that are all rectangles? An amazing example of rectangular prism is bricks and here we have four bricks which are four rectangular prisms.

The 3D version of the rectangle, you may have seen this in your classroom or at home. It's a Kleenex box and the Kleenex box. is a great example of the rectangular prism, it has six sides or faces that are all rectangular, so the secret is that most boxes are rectangular prisms, so here is another rectangular prism and it is a box and it is a shorter box, but it still has rectangles around it and it is a rectangular prism, what more can we say? It's a cool shape, the rectangular prism is the 3D version of the rectangle, it has six sides or faces that are all rectangular and it's just a neat shape to have on hand, I guess I mean, you know, yeah. let's review pyramid cylinders sphere cylinder cones rectangular pyramid prism spheres let's do a little more on the top here we have cubes we can say that because it is the 3d square it has six sides or faces each of them are squares it's cool, do you remember what shape?

These bricks are yes, a rectangular prism, they are rectangular prisms, they are the 3D versions of the rectangle at the top, we have a cone, a cone has a circular base at the bottom and it all comes to a point called the vertex, remember? the shape here at the bottom is three cylinders, they have a circle at the top and a circle at the bottom and everything is smooth. You're doing an amazing job, seriously, great, so what is this higher form? Remember? Yes, it's a pyramid a pyramid a pyramid has a square base, it reaches a vertex or a point and has triangles as sides, remember that last shape here at the bottom?

Yes, it is the sphere, the sphere that is the 3d circle and we. We started with this and we're finishing with this and it's so amazing, hey, well first of all, elephants don't drive, okay, elephants can't get a driver's license and he drives on grass, he's driving on grass. , you're going to ruin. the grass, okay, what's going on here, okay, this is out of control, okay, elephant, I don't want to tell you what you can do, what you can't do, but you can't drive, okay, oh Oh my gosh, okay, now we're next. I'm going to learn about numbersRomans, which is a different way of writing numbers and it was used a long time ago in ancient Rome and it's been used ever since and you can think of it almost as a secret code way of writing the numbers, it's pretty simple. to learn and we are going to review that the first roman numeral that we are going to learn is the roman numeral i and i is one i is equal to one, so if you see an i with a roman numeral is one, the letter v is the roman numeral that means five and the letter it's how you can remember that i is one i is the Roman numeral for one a v is in the number five when you spell it the number five you see it has a v right there so when you think of v you know oh you know what there is a v in the number five written, so v has to be five, now tan is x and we can't think of anything that can remind us of that, so there is nothing to memorize, just when you see the have to get it right one last time here just want to make sure you understand there are only three i is the roman numeral for one v is the roman numeral for five and x is the roman numeral for ten and you have to understand that so we can start playing kind of a game of putting them together and making numbers other than 1, 5, and 10.

So let's get started, so let's practice putting these Roman numerals together. What number do you think it is? You see two eyes. and i is one so the answer is two two i is the number two what about this? one, what number do you think this is? There are three eyes, yes, it is number three. Let's try this one. What number do you think it is? We see two x's and x is equal to ten, so ten plus ten equals twenty. Great job, this is number twenty. This is great, okay, an x ​​and a v, what number do you think the x is a ten, the v is the number five?

Awesome, so what's ten plus five fifteen? Thank you very much for helping now that we have seen how to put some of these together I want to talk to you about two special numbers that are a little different, so you will have to remember them on your own: the first is the number four and the number four is represented with an i and a v and the i is before the v because four is one less than 5, which is v, so remember that with 4 is i v with 9 is similar except that with x 9 is i x x is 10 and i is right before, so nine is i x Well that was really cool, thanks for hanging out and learning them with me, but we're not done yet, we want to go over all the numbers up to 30 just using the numbers and I want to see how much you've actually learned, so if you'll do me a favor as the numbers increase.

I want you to say the numbers with me and we can practice together. Sounds good. Well let's get started. One two three four five six seven eight nine ten eleven twelve thirteen fourteen fifteen sixteen seventeen 18 19 20 21 22 23 24 25 26 27 28 29 and 30. Well, there you have it, a new way of writing numbers. Wow mom, you are doing a great job in your career. I had no idea you were an athlete. Okay, I mean all that fabric wrapped up you're doing great, you're doing a great job just like these kids are doing a great job learning actually, how about this? The next thing we will learn is division.

The division is something incredible. to be able to do it and you will have it all figured out, you will learn how to divide in this video and we will start with a story. There is a boy named Ethan and Ethan loves carrots. carrots so much that he loves to snack on them, he loves it when he eats them, they are crunchy, they are tasty, yes carrots are amazing, in fact I am literally eating a carrot right now as I speak, carrots are great for you carrots with skin they are great for your eyes, they are amazing, you make a great snack and Ethan loves them.

Ethan has two friends with Kevin and Chloe and they start to get hungry, of course they all love carrots because now carrots are the perfect snack. In Ethan's house there are only three carrots there are only three carrots we are going to have to divide the three carrots between the three children so let's find out how many carrots each child gets, you know? aha, each child gets a carrot pretty simple right three carrots three kids each child gets a carrot hey, did you know we just did division? Aha, we just did division. The division is quite simple.

You see, division is dividing a number by any given number. That is, simply dividing a number. Above, let's look at our story again, there were three carrots and we divided those three carrots by three because there are three people, right, all three children love carrots and the answer to how many carrots each child gets is one, three divided by three equals one warning. here is the division sign, this is what it looks like when you see that sign, you could say divided by, so it reads three divided by three equals one, let's try another example of division, let's say there are eight gifts, eight gifts and there are four. women and we want each of the women to receive the same amount of gifts as the other women because we want it to be fair notice the division sign we are going to divide or divide eight by four remember to divide is divide we are going to divide these gifts into four groups same one two three four well, how many gifts does each woman receive? uh, two, each woman gets two gifts, isn't she so cool?

Division is so much fun and it's so easy, remember that division is dividing a number by any given number that's it now it's time for division facts, we're going to learn some pretty interesting facts about division and you're going to say: " Oh my god, like secrets, this is cool, okay, so just look around, okay, make sure.” Okay, so who's clear? Okay, time for division operations. The first fact is that you can never divide by zero. It's true. You can never divide by zero. Even if you break the rules and think, "I'll do whatever." I want you to still never be able to divide by zero, in fact if a teacher ever gives you a test and you see a problem where you have to divide a number by zero right on the test, undefined because that's exactly what that answer would be indefinite, it is impossible. kind of like Mr.

Whiskers'

math

skills. Does Mr. Whiskers do

math

in his head all day? Who knows that his mathematical abilities are not defined? We just don't know. It is impossible to know. You know Mr. Whiskers may know how to do splits. Who knows? It is not defined?. You don't divide by zero, you will never be able to divide by zero, if you ever see any division problems dividing by zero, just write undefined, it's impossible, it's impossible, so write undefined. The second fact is that you can write the division sign in three ways, not just the traditional one. division sign you can write it as the division sign or you can write a division problem with the bar or with a horizontal line, for example, look at this 12 divided by 3 is equal to 4, that is the original division sign, the one that you may see more regularly, but here is the same equation written another way twelve divided by three equals four it is still a division sign but it is a slash means the same thing as the original division sign remember that the division sign It can also be a horizontal line twelve divided by three equals four which looks like a fraction, doesn't it?

The line in a fraction means divided by these are the three ways you can write the division sign. It's quite interesting, very well, the final fact is that okay, this is so amazing that you can reverse the number of. groups and the number in each group and the division problem is still true, for example ten divided by two is equal to five and you can reverse the two and five and it is still true, that means ten divided by five is equal to two, it's not that interesting ten divided by two equals five and ten divided by five equals two, you can reverse the number of groups and the number in each group and it's still true or look at this eighteen divided by six equals three remember that we can reverse the number of groups and the number in each group and it is still true, so we could change the six and the three and it is still true, so 18 divided by three is equal to six, the six and the three can be reversed, so 18 divided by six equals three and 18 divided by 3 equals 6 pretty.

Great, those were some interesting facts. You know, the split is a great moment. Division is dividing a number by any given number. It's a lot of fun and we hope you learned a lot in this video. Wow you completed the video it is so impressive! You may notice that there is a circle right here on this video page that you can click on to subscribe to our channel or you can click on this rectangle to go to another one of our videos, but keep learning, learning is great.