Does blogging about your blog count? If so, this is post No. 61. I dunno. Hence, the asterisk.


Reflections in the Why debuted, in earnest and to much fanfare, in September 2011. Initially, I set a personal goal of publishing one post per month. Expect No. 62 in October 2016.

This look back comes at this time because (1) I’m introducing a group of teachers to the mathblogosphere on Friday, and (2) I missed the obligatory 2012 year in review post.

According to my WordPress.com annual report, the top two search engine terms that land users at my blog are tarsia and…


My most viewed post? My 7-year-old daughter keeps beating me at Spot it! In this post, I wrote about walking away from the very same thing that, as it turns out, drives much of my blog’s traffic:

I finally asked, “Why am I doing this?” Okay, so the game might be fun for some students, but would it increase their conceptual understanding? Of course not. We’re talkin’ about practice.

And isn’t it ironic, don’t you think?

I tend to write what I would like to read. The bloggers that I enjoy reading the most:

If tarsia or practice landed you here, in the same spirit of, but not necessarily in the same league as, the list above, I encourage you to check out the following:

My 7-year-old daughter keeps beating me at Spot it!

I have an excuse. While playing, I start thinking about the mathematics behind the game rather than the cards in front of me.

The goal of Spot it! is to be the fastest player to spot and call out the matching symbol between two cards. There are 55 cards, each with 8 symbols. Between any two cards there is one, and only one, matching symbol. How did the designers accomplish this? Sue VanHattum explores this question on her blog, Math Mama Writes.

In addition to thinking “How did they do that?” I started thinking about creating a smaller math version of Spot it! What if, rather than symbols, students matched equivalent expressions? A game might consist of 21 cards, each with 5 expressions (e.g., \sqrt {64}, 2^{3}, \dfrac {4} {3}\div \dfrac {1} {6}, \left( -2\right)\left( -4\right), and 8).

I began by creating 7 cards, each with 3 letters. While I was trying to create 13 cards, each with 4 letters, I finally asked “Why am I doing this?” Okay, so the game might be fun for some students, but would it increase their conceptual understanding? Of course not. We’re talkin’ about practice.

I have decided to walk away from creating these types of activities. It won’t be easy. The card stock! The laminator! The paper cutter! I love these things more than a grown man should. I’m quitting. Cold turkey.

But first, check out my latest Tarsia jigsaws…

factoring trinomials tarsia (normal)
factoring trinomials tarsia (larger)
factoring trinomials tarsia (solution)

rational exponents tarsia (normal)
rational exponents tarsia (larger)
rational exponents tarsia (solution)

Tarsia Jigsaws

Last year, one of my former student teachers told me about Tarsia, a software program that allows teachers to create jigsaws (and more). He remembered that I created similar jigsaws using MS Word (no small feat) and experienced this joy himself as a new teacher. I wish I knew about this tool several years ago.

Tarsia includes an equation editor for entering matching expressions. Teachers may also enter distractors so that corner and edge pieces are not easily determined. The activity cards are scrambled when outputted, ready to be cut out by students.

Here’s one that I quickly created:
logarithms jigsaw (normal)
logarithms jigsaw (larger)
logarithms solution

In my classroom, I often used jigsaws to review a topic. In addition to providing students with opportunities to practice, these activities get students talking mathematically. As a teacher, I am able to listen to students making mathematical arguments about whether or not pieces fit together and observe them checking and revising their work. Also, eavesdropping on these mathematical conversations will tell me if there are topics that need to be discussed further (e.g., rational exponents).

Formulator Tarsia (for Windows only) can be downloaded here.