Click on this link for my Number Sequences Posters.

If you are a math teacher like me, you are more interested in getting students excited about math or doing math yourself than decorating your classroom.

My Favorite Mistakes posters hanging at the top of the glass panels. August 2021. To see more photos of my classroom, read my Ideal Math Classroom blog post. |

This is what the sequence of the perfect squares could look like in your classroom.Assuming your classroom has a green chalkboard. |

### I don't like to decorate

My classroom is so plainly decorated that one day during the 3rd week of school, my principal popped in for a chat and asked when I was going to decorate my classroom. "It *is* decorated," I said. We had a good laugh.My classroom circa 2014 (down the hall from my current classroom).The bulletin board is pretty bare. This was during pre-planning week, but the bulletin board didn't change much during the year! |

I no longer have a bulletin board because, in 2018, they removed all of the math classrooms' bulletin boards and replaced them with large glass panels that we can write on with dry-erase markers! Read more about that in my Ideal Math Classroom blog post.

My classroom circa 2019. The bulletin board is gone andhas been replaced by glass panels (with a blue background).We write on them with dry-erase markers! |

*Read more about my classroom with all of the dry-erase surfaces in my Ideal Math Classroom blog post.*

### Purposeful Decorating

One type of decorating that I really like is putting number sequences on the wall.

I have a list of the

*across one wall, the*

**first 20 perfect squares****across another wall, the**

*first 20 perfect cubes***on the third wall, and all the**

*first 20 powers of 2***on the fourth wall.**

*prime numbers from 1 to 100*Powers of 2 posters hanging above the glass panels. August 2021.To see more photos of my classroom, read my Ideal Math Classroom blog post. |

My classroom when I lived in Venezuela circa 2010. It was a science classroom with very high ceilings. Since this photo was taken, I changed the font and added a border to look fancier! Get all four sets of sequences here. |

Each sequence is in a different color.

- red = perfect squares
- green = perfect cubes
- black = powers of 2
- pink = prime numbers

Each sequence is on 12 to 16 sheets of white letter-sized paper. I laminated them so they could last longer – sometimes, I had to take down all of my decorations so they could paint over the summer.

Perfect Squares posters hanging above my whiteboards. August 2021.To see more photos of my classroom, read my Ideal Math Classroom blog post. |

The great thing about having all four sequences in the room is that you can refer to each list by its color. And they lead to some great class discussions such as,

While I initially posted the sequences in my classroom because I enjoy looking at sequences to find patterns, I quickly found that they came in handy during various times of the year. One year, the discussion about whether or not x^3+y^3=z^3 and Fermat’s Last Theorem led to me discovering that there is a musical called Fermat’s Last Tango. I even bought it on VHS (I’m aging myself here) and showed it to my students during class!

Another fun pattern that students often notice with the perfect squares (1, 4, 9, 16, 25, …) is the following:

Occasionally I will have a student look at them and say, "oh! That's not equal?!" These kinds of comments always lead to good discussions.

I keep adding more "favorite mistakes" as I think of them. Currently, I'm up to 16 mistakes! Check them out here! Click here for a FREE SAMPLE.

- “Which numbers are in both the red list (perfect squares) and the green list (perfect cubes)?”
- “Can you find 2 numbers in the red list (perfect squares) that add to another number in the red list?” The answer to this would lead to a Pythagorean Triple.
- “Can you find 2 numbers in the green list (perfect cubes) that add to another number in the green list?” In other words, you’re asking if x^3+y^3=z^3 which could lead to discussions about Fermat’s Last Theorem and some mathematical history.
- The black sequence (powers of 2) can lead to discussions about exponential growth. For example, “Would you take a job for 10 days if you were paid $2 on the first day, $4 on the second day, $8 on the third day, etc.?” You could point to the black list (powers of 2) to see how quickly a sequence grows when you double the number each time.
- The pink sequence (prime numbers) are helpful to have when you are simplifying radicals (e.g., “simplify √116.” Students can quickly figure out that 116 is 4×29, then the question becomes, “Is 29 prime?” Students can refer to the list of prime numbers to see that 29 is prime, so √116=2√29.

Prime Numbers posters hanging above my whiteboards. August 2021.To see more photos of my classroom, read my Ideal Math Classroom blog post. |

Perfect Cubes posters hanging above my whiteboards. August 2021.To see more photos of my classroom, read my Ideal Math Classroom blog post. |

Another fun pattern that students often notice with the perfect squares (1, 4, 9, 16, 25, …) is the following:

1 + 3 = 4

4 + 5 = 9

9 + 7 = 16

16 + 9 = 25

*If you’re interested in my sets of posters with each of the four sequences, go here.*

### Favorite Mistakes posters

Something else I have put in my classroom to elicit discussions is my "favorite mistakes" posters. I show students several common mistakes with a large slash through it to show them that those steps are illegal. ðŸ˜‰Occasionally I will have a student look at them and say, "oh! That's not equal?!" These kinds of comments always lead to good discussions.

I keep adding more "favorite mistakes" as I think of them. Currently, I'm up to 16 mistakes! Check them out here! Click here for a FREE SAMPLE.

You might wonder if I take them down before assessments. I don't. You would be surprised (or maybe you wouldn't) by how many students don't pay attention to them and still make these mistakes during assessments.

### How do you decorate your math classroom?

These "favorite mistakes" are helpful to have on the wall because I can refer to them when I'm teaching and want to caution my students about common errors. |

My Favorite Mistakes posters hanging at the top of the glass panels. August 2021. To see more photos of my classroom, read my Ideal Math Classroom blog post. |

Click on this link for My Favorite Mistakes Posters. Click here for a FREE SAMPLE!

Click on this link for my Number Sequences Posters.

Click on this link for my Number Sequences Posters.

### You may also be interested in these blog posts:

### How do you decorate your math classroom?

*Let's continue the conversation. Join me in my Facebook group.*