Welcome to the 81st edition of Math Teachers at Play (MTaP) Blog Carnival. I am extremely exited to host this post in my favorite month of the year, December. In case you don’t know much about this carnival I encourage you to read more (click here and here) and maybe you could be the next host. So, lets get started! ^_^

*Understanding 81: *Firstly, 81 is not prime because it is the square of 9, or the fourth root of 3, which make it really fun to play when learning logarithm in different bases. (Thus it is a composite number). And it is an odd number.

An interesting fact is that 81 is a tribonacci number (sounds a lot like Fibonacci) – the sequence of tribonacci numbers start with 3 predetermined terms (0,0,1) and each term afterwards is the sum of the preceding 3 terms. Thus the sequence starts like this: 0,0,1,1,2,4,7,13,24,44,81,… (you can go further if you want to see how fast the numbers go).

Now the maths posts, but first thank you very much for all the posts submitted to us.

1. In the article Fourth grade SDC class achieves tremendous gains in math using newspapers we see how much we can do with less extra-materials around us. The article presents nicely the story of Sylvia, which used newspapers and a lot of creativity to make children properly **understand numbers and their properties**. Also she made them like mathematics from an early age, which is extremely important.

2. It is great to see a parent understand how important it is for their children to think outside the box. Here is a great **measuring principle** in an easy exercise that shows how important using mathematical concepts to daily activities it is: Thinking outside the box (math lesson) .

3. One of the first things we need to understand about bigger numbers when we are in primary school is **place value**. This is a crucial mathematical concept, and the Evil Math Wizard gives us important advice at handling this topic: letting children develop their own approach. Enjoy the article Place Value – What Comes Next?

4. Playing with a 100 chart can be very creative. Here are more ways to play with this unique maths tool : Math Debates with a Hundred Chart. So take your chart from under the bed and start playing ^_^

5. Knowing how other countries teach different concepts can influence the way we teach ours. This is what happened TBAAD after finding more about the Japanese model of **Bansho**. Find out how this changed his way of teaching the **distributive property of multiplication** : Distributive Property of Multiplication… Oh, my!

6. How hard is ‘reading’ the clock? Well, it is very challenging at first and gives a lot of headache to children and also to teachers. But it is extremely important to** understand time** and it is a skill that it’s used daily, so it is worth the struggle. But the article Deconstructing Time gives us great tips to make this process an interesting and fun activity for everyone. Moreover, it is based on making children understand things in a specific order, giving them time to **adjust to the new concepts**.

7.**Functions** are an important concept that sometimes students don’t completely understand and this influences the way they handle the more advanced topics. Here is a great article by Mrs. E that gives great tips for teaching **functions notations** : How I Teach Function Notation. I have to admit that I would have loved to see my teacher draw hearts or smile faces to make the concepts understandable.

8. On the same topic (functions) I consider that the Domain and Range of Inverse Helpsheet gives you great tips for understanding the existence of **the inverse of a function** (and you can also download it).

9. The Dot and the Line Math Trek presents an incredibly fun and creative maths game Math Trek. Also, it shows how nice and fun it can be to explain even **integration** and **differentiation** using it, and children seem to enjoy it:

10. On a little more advanced part we have a great article about quasi-random numbers and the difference between them and the pseudorandom numbers : Quasi-Random Christmas Tree. It gives interesting example that it gives you a little sense of the oil and gas extraction and from this** practical (applied mathematical) concepts** the article goes to Christmas Trees (the problem of decorating the tree in a more optimal way, so that the ornaments are distributed without large gaps), really enjoying.

11. The article It’s Christmas Time gives us a nice **list of maths activities and games** for all types and ages. They are perfect for Christmas period and give you a a good understanding of maths concepts such as graphs, but also on applied maths concepts and computer science such as coding.

11. Have you thought about what kind of problems can appear at a job interview for someone interested in working in STEM fields? The Bridge Crossing Problem is such as example, and the article explains the problem and also gives us a javascript program that varies both the problem size and the times given so that users can see how well their strategy works on different problem sets. The author said that *“I decided to write about the problem because, similar to the reason the question is given in interviews, the problem is a good way for people (both students and adults) to try to break a problem down to its core concepts and devise a strategy for solving it.” *Great and useful idea for all of us.

12. Have you ever thought why sometimes maths is school is about giving lots and lots of formulas and rules that are forgotten immediately after exam? The author of the project Unizor tells us something extremely important: *“I’d like to emphasize the importance of development of students’ minds as a main goal of study mathematics in schools as an opposite to filling these minds with mathematical information (like formulas, rules, properties) which is usually forgotten immediately after passing exams. As a development tool, mathematics presents a huge opportunity through its logical approach, creativity in solving problems and proving theorems. That’s the reason I’ve started UNIZOR.COM “. *I believe this is a great approach on maths, and the blog has a lot of wonderful articles that cover some great advanced topic from probability and combinatorics, but not only.

13. We find it really strange to put** art and mathematics (or sciences in general) together**, but I am pleased to see that more and more people understand the beauty that appears when you combine this 2 concepts. And Taking your STEM to STEAM: 8 Ways to Add the Art offers ideas for Math (and Science) teachers who want to incorporate the arts into their curriculum. Think carefully at this important step Math Giraffe encourages us to take and understand the importance and flexibility it gives to children.

14. On the same topic (changing the way we teach maths), we have a great article : Educate for the Future – Teach Concepts. It encourages all of us (parents or teachers) to show children concepts and make them understand the significance, and not focus on learning things for tests. Moreover, it makes us think of things we need to change in our practice because of the development of computers and their speed when it comes to solving equations, but their lack of **understanding concepts**.

15. How important are words in maths? You will be surprised to find out that we make word mistakes daily when it comes to maths concepts. The article Faux Diamond explains us the difference between rhombus and diamond, also portraying when we use the wrong term in day to day life. Moreover, it makes us all understand how important it is to use the write word in maths from the very beginning: “*if you are an elementary grade teacher, please use the correct mathematical language because a middle school math teacher will thank you; a high school geometry teacher will sing your praises, (see song below) and a college math teacher, like me, will absolutely love you for it!” *

16. Choosing a **maths game** for the class can sometimes be a little hard. We have to pay attention to its difficulty, creativity and more. Moreover we have to be very careful to make it interesting and fun for the children and also present the maths concept correctly. Checklist for Great Math Games gives us a nice list of things a math game should have to be a ‘quality math game’.

These are all the articles for this month, if you feel that something is missing let me know in the comment box bellow. Also, you can let me know of any other interesting things happening in the maths world in December.

Just before going I still have a couple of things to share with you:

– A couple of bloggers decided to do a sort of **Advent Calendar Maths** related with really nice post every day from 1st December to 23rd December. This is the 1st entry: IHeart Math Holiday Hop, don’t forget to check all the other posts until now and encourage the idea.

– Carnival of Mathematics had its 117 edition this month and great articles. Don’t forget to check it.

And this is the end of the Carnival. Hope you enjoyed it, because it was a great experience for me and I am thinking of hosting it again. If you want to be a host click here and help us spread ‘Maths LOVE’ .

Thank you for reading. Have a great weekend. Enjoy the holidays and Christmas! Wish you the best and don’t forget that maths is everywhere. ^_^