Two new reference units have been added to the site, which teachers may want to explore for the next coming school year as supplemental materials.

Simplifying Radicals

Simplifying radicals is an area of Algebra that students often find frustrating (and also pointless). In this unit, we discuss first of all the reasons why having standard rules for simplifying radicals isn't pointless, and then we go into detail on many of the rules for simplifying different kinds of radical expressions, including some less common but interesting radical simplifications!

Significant Figures

This unit covers another area of math and science study that many students consider to be pointless. Again, we address the question of why sig figs really are useful, and then explain the rules for finding significant digits,  and the rules for applying arithmetic operations like addition and multiplication when using significant figures. There is also an explanation of the difference between measured and non-measured quantities, as well as some word problems requiring proper use of significant figures.

We hope you find these units helpful!

Good morning! It was pointed out to me yesterday that this is a palindromic week - all the dates this week are palindromes:

6-12-16, 6-13-16, etc.

Of course, it's not a true palindrome unless you remove the hyphens (since they make the number non-symmetric): 61216, 61316. Also, it's not just this week; it's any date this month in the teens: 61016 through 61916.

Even though I didn't know it was a palindromic week, we have two new Professor Puzzler posts about palindromes:

Palindromic Squaring

How many Palindromic Squares

On a related subject, I wanted to share with you one of my favorite words about words: semordnilap.

A semordnilap is a word which, when spelled backwards, is also a word. For example, STOP is a semordnilap, because when you spell it backwards, you have POTS, which is also a word. Semordnilaps are important in one of the word games over at Quote Puzzler. In fact, there's even a list of all English-language semordnilaps over there: Semordnilaps in English.

And by the way, if you haven't done so yet, you should reverse the word semordnilap to see what you get.

Which means, of course, that even though palindrome is not a palindrome, semordnilap is a semordnilap.

First of all, since there's been so much hype lately about Star Wars, did you know that there is now a Death Star Perplexus? What? You don't know what a Perplexus is? It's a 3-dimensional marble labyrinth game. If you've never played with a perplexus before, you should give it a try!

You may have noticed that last week a new menu option showed up at the top of the page. It's called "Resources" This option was added because we have some new resources that are tough to categorize under any of the other headings, so it made sense to have a place to compile all of these in one place.

Here you'll find our product review blog, our Vortex pages, and the following new features:

Alphabet Lists: This feature was designed to help teachers and parents who are teaching the alphabet to their students/children. You can choose a letter of the alphabet, or a category, depending on whether the alphabet letters are the primary or secondary focus of your teaching.

Population Explosion Simulation is a simulation based on a question Professor Puzzler was asked recently about how quickly the human population could expand.

Gravity Train Simulation is based on an interesting notion of drilling holes through the earth so that trains would be able to pass in a straight line from one city to another. Although the notion seems crazy, and is certainly way beyond our current technological capabilities, it's a fun concept to consider.

Recently we've had a report of a couple of our games no longer functioning properly in some mobile devices. We're working on tracking down the source of those glitches. Some have been repaired, others we're still working on. If you have a mobile device, and one of your favorite games is no longer working the way it used to, please let us know about the trouble you're experiencing. You can contact us most easily by clicking the "Ask Professor Puzzler" link at the bottom of any page. Be sure to mention which game you're having difficulty with, and explain in as much detail as you can, the problem you're having.

Speaking of Professor Puzzler, the "Ask Professor Puzzler" blog is really the new and updated version of an old blog called "Ask Doug" that the site administrator started back in 2005. Over the course of the next few weeks, we'll be taking the contents of that old blog and re-publishing the posts on Professor Puzzler's blog. In most cases, the publication dates will remain in the distant past, so you won't actually see most of the posts crop up on the main page of the Ask Professor Puzzler blog. However, once in awhile, we'll find one we think is particularly interesting, and we'll update it and republish it with the current date. For example, this morning we just republished the blog post about The Diameter of the Internet.

The "Ask Professor Puzzler" blog has become a very popular point on the site in the last few weeks. Yesterday, for example, more than one third of the people visiting The Problem Site were people who were looking for information on the Professor Puzzler blog!

This is great, but at the same time, all those people who came to read one page and then left again - we wish they knew about all the other resources on the site. Accordingly, we added a new game to the Professor Puzzler blog. At the bottom of the first post on each page of the blog there is an inline game called "The Daily Scrambler." It's a very simple game in which you have to unscramble one word. When you finish, the site will show a "Game Over" window that invites the player to try other games on the site. We're hoping this will become an incentive for people to stay longer on the site.

This new game only appears on the Professor Puzzler blog, so if you want to play the new Scrambler each day, add the Professor Puzzler blog to your list of daily visits!

Many of our members come back day after day to play specific games. Your favorite games might be Secret Word and Scrambled Word. Or maybe you prefer logic and strategy games like Trio Match, Entrapment, and Diamond Slide.

And you might be one of our many Daily Puzzle addicts.

Up until just a week ago, if you had multiple games you liked to play, every time you come to the site, you would have to look up each game individually on the game page, and then go back to look up the next one when you were finished the first.

We have added a great new feature called "My Game Sequence." This feature lets you select the games you want to play, in the order you want to play them. Once you've set up your game sequence, all you have to do is click "My Next Game" each time you finish one game, and you'll automatically leap to the next game on your list.

This feature comes with Pro Membership, which gives you access to a lot of other features as well. For a $5.00 one-time fee, that's a great deal!