Algorithms Education TPT

How Teachers Pay Teachers’ search algorithm works

First a disclaimer. I don’t have any secret information from the company itself. This article is based on general information about how commercial search engines work and then reasoning about which of these apply to Teachers pay Teachers’ search algorithm plus some experimental findings.

Search algorithms of other online commerce sites

There are tons of online shops and search algorithms out there, and first we have to pick some of them for a closer look. We want those sites to have some things in common with TPT such as

  1. The site is selling something
  2. There are a lot of individual sellers on the site who have their own shops.

So, we won’t be comparing TPT to Google, however interesting search engine it is because it’s not selling products directly to consumers. I have picked three large online shops to compare: Amazon, Etsy, and eBay. All these three are public companies, TPT is privately owned. To set these to some sort of scale: Amazon has over a million workers, eBay has over 10,000. TPT has over 2,000 and Etsy over 1,000. So, you could expect Amazon’s algorithm to be the most refined, because they have more resources to put into it. For the rest of the companies, the fine tuning of algorithms depends on how much effort they put to them. But for purposes of this article, we assume that TPT’s search is about the same level as eBay’s and Etsy’s and all those look up to Amazon’s, thus it’s important.

Below, I list factors that matter for the search algorithms in some of these sites. After each factor, there are one or many of these ecommerce sites which utilize these factors. This information is based on sources that can be found from the end of this post. Note that if a site is not listed, it doesn’t necessarily mean that it doesn’t use that factor. This list is in no particular order. 

Title relevancy

(Ebay, Etsy) How well the product title matches the thing the buyer is looking for. This is more important if the buyer is using longer search terms, it would be hard to rank high by using some very general search terms like “fractions”, even if some people may do that exact search. The best long term strategy is to use titles that describe your product the best way, so use all the words that are relevant as long as it’s easily readable to a human buyer and don’t repeat words in the title. Algorithms generally punish repeating keywords too much. 

Seller authority or track record as a seller

(Amazon, Ebay, Etsy) This is definitely a ranking factor in all those marketplaces. In TPT context, that would mean the quality of your shop. TPT keeps the seller’s star rating at the upper corner of every shop’s page, so surely they think it’s important. That being said, TPT’s ranking system has been quite monotonic for years resulting that almost all old sellers have full star ratings. However, the system has been changed in order to get more variety to feedback. From all of that, we can reason that for e-commerce, shop reputation is generally important. Maybe it isn’t that important in TPT yet but surely it will be in the future. 

Organic sales

(Amazon) An organic sales is when a buyer searches something, finds and buys it. If the buyer finds the product via promotion, that’s not an organic sale. There is no 100% way of knowing if TPT distinguishes organic and promoted sales in future search results, but it’s something that may have some effect. 

The price

(Ebay) The price most likely affects the Amazon search too, as the Internet is half-full of sites about how you find the right price point on Amazon. It’s reasonable to believe that this also affects Teachers Pay Teachers’ search, but from an ecommerce site’s point of view it’s not that simple. People will generally buy cheaper products easier, but if products are too cheap, the revenue is harder to get and people tend to think less of products that have too low price. So, an intelligent search algorithm designer would favor middle priced products.

Off-site sales

(Amazon) Are you bringing more customers to the site by advertising your product? Then, you are a good seller! Maybe you even get some boost in the search engine. My own experience with TPT is that I rarely get sales from social media sources such as Pinterest. But there are times when I focus more on Pinterest marketing and more traffic from Pinterest is coming to my shop at these times. Even if those people are not buying right there and then, also my organic sales are higher at these times. So, it might have an effect. (Wishlisting is also a possible contributor here.)

Quality of product description

(Ebay) This is easy to implement in TPT, because you can always write a good product description. Some of the other factors are not in seller’s direct control. A good description has everything you need to know about the product and also all the relevant keywords. But again, stuffing the same keyword over and over again is punished nowadays. 

Conversion rate

(Amazon) Conversion rate is a ranking factor on Amazon and because TPT lists it as one of the product statistics it’s probably a thing in TPT, too. Logically, the bigger, the better.

Listing of terms of service

(Ebay) This idea of being clear about terms and service could translate into TPT language in licensing policy. If TPT takes this to account, it is likely to favor those products that have a clear licensing policy written down in the description. 

Listing quality

(Etsy, Amazon) If a buyer makes a search and then clicks a product on the listing, that counts towards listing quality. In TPT, if there is such a feature, good thumbnail pictures will help you with this.


(Etsy) Other things being equal, a new and fresh product is better than ten years old. It may not feel that way because other factors tend to favor the older ones. I have heard rumors that updating a product in TPT would have a positive impact and that is in line with recency. 

Other interesting search factors from these sites:

  • Words at the beginning of titles are considered more important than words at the end.
  • Past intellectual property infringement issues can have a negative effect.
  • Store location in relation to buyer
  • Shop’s information page about the seller

Experimental findings about Teachers Pay Teachers’ search algorithm

Because your search history may affect the results I did some test searches when I was logged out of the site. If you use some popular search term, the results in the first page have pretty much everything right, so you really start to see more interesting patterns when browsing more pages down the search results until the matches are not “perfect” any more. Here is something I found: 

This is from page 9 with a search “Adding and Subtracting Fractions with Unlike Denominators”. This may sound a bit arbitrary thing to search, but in fact it is one of the popular search terms every now and then. Grade level at this search was three. (There is no actual reason for that, I forgot to take it off after the previous test.) I didn’t take the whole page in the pictures, but the idea is that most of the resources have only a couple of stars, while the resources in page 1 would have hundreds of stars. But there are few exceptions, pointed out with arrows. 

It took me a moment to figure out what was dropping these resources down. I have covered the seller names in the pictures, but I checked them and they were perfectly top rated, established sellers. The problem was that these products have very few pages. The ones that cost $1.00 had only one page per product. So, the lesson is, that if you have very few pages accompanied with a high per page price, your resources will not do well in the search. 


Based on logical reasoning, we could expect at least the following factors to have something to do with the order of Teachers Pay Teachers’ search results:

  • Title relevancy
  • General shop quality
  • Organic sales
  • The price
  • Off-site sales
  • Product description
  • Conversion rate
  • Clear listing of license terms
  • Customer clicks in search listing
  • Recency
  • Price per page

Hopefully this article was helpful! Have you experienced some weird rankings in Teachers Pay Teachers search? Leave a comment!

Sources: Amazon’s A9 algorithm, eBay optimising listings, How Etsy search works.

Education math TPT

Irrational Numbers – More than Infinite

Irrational numbers are numerous and yet, you can’t think of any of them. “But I can think of pi!” you might say to yourself. Well, ok. How does it go, then? Is it a fraction of some number we are already familiar with? No it isn’t.

Today, we have many things that are absolutely too complicated to understand completely, such as quantum physics. Unless you spend your whole life researching it, of course. But there is something much more familiar yet still surprisingly complicated: the irrational numbers.

Let’s think of it this way: You start in the morning with a notebook and start writing random decimals to a number. For example, you start with 0.628465963 and add random digits until you have five pages full at lunchtime. What you now have in your hands, it’s a rational number, not irrational. That’s because you can write it as a fraction. The numerator will be all the digits after the decimal point and the denominator is a power of ten; it has one and as many zeros as your number has decimals.

So, any number you can create decimal by decimal will be a rational number. Irrational numbers will look like special cases, square roots etc. And you would probably think: “Well, there must be only a limited amount of irrational numbers, then.” 

But that is not the case. There are a lot more irrational numbers than rational numbers. That’s where the infinity really comes into play. If you think of a decimal number as an endless journey to infinity, digit by digit, you realize that every time we take the next step, there will be ten directions we can go. And at the next step, again ten different directions. So numbers we get this way is countless. And only rare cases are rationals, like those that happen to have repeating decimals. If you want a rounded estimate, 0% of all real numbers are rational, the rest about 100% are irrational. 

Whoa! That was something. If you want to familiarize with the subject more, I made a free pdf material that you can download from my tpt shop. It has a concept understanding crossword and a story about how we even know that irrationals really exist.

If you need to teach this subject to let’s say, eight graders, there is presentation & worksheet bundles in my shop: 

Version for Google Slides™

Version for PowerPoint

These are essentially the same, but one has presentations for PowerPoint and the other for Google Slides™.

Hopefully you enjoyed this article! Irrationals are so intriguing, because they are easy and very complicated at the same time. If you want to challenge something, please leave a comment. 

The writer used to be a math teacher in Finland and has a master’s degree in math.

Education TPT

Free STEM Worksheets for Middle School

Again, 10 fresh free materials from different Teachers pay teachers authors! This time the focus is on stem worksheets for middle school.

Forward or Backward? Multi-Step Math Word Problems (grades 5-8)
Forces students to think wether they should start solving word problem forward or backward

Science Literacy Monster Fish (grades 5-8)
This resource combines literacy and science. Extra mention for the coloring picture that I find very artistic!

The Sun Worksheet Activity (grades 5-8)
Several fill-in activities about the Sun.

Solving a Problem in Science (grades 5-9)
It’s always useful to recall how problem solving in science works.

Elements Compounds and Mixtures Classification of Matter (grades 5-11)
The given grade level distribution is quite wide, I would suggest this for middle school rather than high school. However, clear and useful worksheet about matter.

Area of Polygons Maze (grades 6-7)
Students calculate area of each polygon an based on the result choose the right way to continue.

Weather Patterns, Factors, and the Atmosphere Word Search (6-7)
Word search puzzle about weather and atmosphere.

Density Puzzle, St. Patrick’s Day Themed (grades 6-8)
The aim of the game is to calculate densities of coins and get letters as a result. Looks fun and creative, the workflow might require some explaining to students.

Unit of Work Facts and Fishes (grade 7)
This material is 55 pages long! I first wondered how this is even possible, but then realized that the publisher is an institute from Australia.

Powers Worksheet (grade 8)
Worksheet for 8th grade math about integer exponents. Answers included

Hopefully you will find these materials useful!

Image by Arek Socha from Pixabay

Education TPT

Free Valentine’s Day Products in TPT

February and St. Valentine’s day is coming, and especially with younger students it’s time to use themed materials! I found also some fresh materials for older students. I divided these into three groups: Primary school, Middle school (and up) and for your own creations. Some of them are even for commercial use. Enjoy!

Primary school

Valentine’s Day Flashcards in Spanish (grades K-5)
Cards with Spanish words, related pictures and English translation.

Heart Tiles – Memory Game (Not grade specific)
As a memory game, this suits better for kindergarten or primary school. Nevertheless, I wanted to include this because I really like the grapchis. Creating 15 different shapes from heart is not that simple.

16 Free printable Valentine’s Day Bookmarks (Not grade specific)
Valentine & love themed printable bookmarks

Heart Mandalas for Valentine’s Day: Art Lesson for Grades K-7
Detailed instructions for art lesson about hearts and mandalas.

Middle school and up

Romeo and Juliet Persuasive Letter (grades 9-12)
Contains one page introduction to Shakespeare and Romeo & Juliet and task to write a persuasive letter to relatives of one of them. Certainly creative way to approach this love story!

Science Valentines for Middle School (grades 5-9)
16 mini Valentine cards with science puns that are suitable for middle school students. Includes colored and black and white options.

For your own creations

Valentine’s Day Game Board (with editable game cards) (grades 2-6)
Valentine’s day themed game board with cards. The aim of the game is to ask questions and to answer them. Cards are in PowerPoint format and you’ll have to type the questions before playing.

Valentine Borders and Frames Collection (Not grade specific)
Huge pack of borders even for commercial use, if you just mention Willow Designs. Definitely worth downloading!

Valentine’s Day Clip Art Set (K-6)
17 png images in a zip package for decoration purposes.

Valentine’s Day Task Card Template for Commercial Use (Not grade specific)
Four identical task card templates for letter size products. Free for commercial use as long as the shop is mentioned.

Lower part of the image by stux from Pixabay (Cubid by me)


10 free posters in Teachers Pay Teachers

Today, I’ll be listing posters that you can print out and hang to your classroom wall. I can tell you there are many of them even if you take only the new ones into account, so I’ve done some picking and chosen those that look beautiful to my own eye. Subjects vary from mathematics to English language art and from sexual health education to physics. Resources are ordered by grade. Most of the posters are not that grade specific, but I’ve omitted kindergarten and preschool materials. Sometimes I’ve narrowed down very wide age ranges, that is represented by /.

Habits of discussion (Not grade specific)
Short guide for students to communicate respectfully.

Order of operations (grades 1-8 / 4-8)
Great when studying order of operations including powers and parenthesis. Description says for grades 1-8, but I’d say this could be confusing before powers have been introduced at all.

Ground rules for sexual health education (grades 4-12)
Encourages students to be respectful and speak about themselves or in general level, not about others.

Branches of Mathematics (grades 5-10)
Simplified interpretation about different fields of mathematics. Helps bit older studets to form a picture what mathematics can be.

Author’s purpose posters (Not grade specific / middle school and up)
Five posters each presenting one author purpose. It says on the description that this is not grade specific, but I think it fits best when you start reading longer and more diverse texts, so not in the very first grades.

Just Right Books Posters (Not grade specific / middle school and up)
Guides students to choose the right level book (I can imagine that is not always easy). Again, middle school and up is my opinion, not grade specific is author’s view.

Law of reflection (7-12)
For physics, law of reflection. Clear poster and worksheet is also included.

Shakespeare’s poets (grades 9-12)

Six Shakespeare’s poets with beautiful backgrounds. Also available in black and white.

Organic compound concept map (grades 11 – higher education)
Colorful and clear concept map. Note that this is in jpg form.

A Christmas Carol Character Profile Posters (grades 8-12)
Seven posters each presenting one character: Ebenezer Scrooge, Bob Cratchit, The Ghost of Christmas Past, The Ghost of Christmas Present, The Ghost of Christmas Yet to Come, Jacob Marley and Tiny Tim.

Hopefully you will enjoy these and other beautiful resources!

Education TPT

10 free puzzle downloads in TPT

I’ll be listing here 10 new free puzzle resources from Teachers Pay Teachers. Grade level is mostly from upper elementary to middle school, so there is no kindergarten/preschool resources in this list. Most of them are very recent, but there might be slightly older resources among these to make it full 10. List is ordered by grade level.

Word Search Activity – “Autumn Words” – Fall – Grades 3-4
The title (which is in fact longer) says it all

Animal picture puzzle task cards (3-5)
Find a value for each (cute!) animal

Halloween Word Search Puzzles (3-7)
Yes, it’s October and I’m sure you are already filled with pumpkins, but I got one Halloween relater resource for you

Word search puzzles Canada (grades 3-8)
Three word search puzzles about cities, mountains and rivers in Canada. Answer key is also included and if you want to, you can colour the flag on the cover page!

La Fecha (4-12)
Spanish cross wordpuzzle

Pirate math polar buried treasure (grades 6-8)
Title mentions math, I’d say you also need some skills in English language, especially about common phrases. But looks interesting!

Introduction to Fiber Optics (Grades 6-11)
I’m always a fan when something more specialised comes along, such as this introduction to fiber optics. Same seller had other similar products too, but I’m only listing one per seller here.

Pirates & Cannibals logic puzzle (7-12)
This is listed under computer science, but it’s purely logic puzzle. I think you could use it with slightly younger students.

Logigramme (Grades 9-12)
Logic puzzle in French! It says grades 9-12 but I think it would suit for younger students too, if they have some basic French vocabulary already.

Common polyatomic word search tile letter pattern (11-higher education)
I have to admit that I didn’t quite get the concept on first read but hey, this was for smart people! I’m looking forward to see what he produces next.

Enjoy these and other free resources!