Fraction Builder

I submitted Fraction Builder to iTunes yesterday and it was approved in less than an hour!  It is so amazing to me what great service Apple offers to developers.  I certainly appreciate the way that the App Store provides access to my work to students and teachers all over the world.


In most of my math apps I try to make them icon-based so that language skills are not critical for working with concepts.  Fraction Builder has a series of icons across the top of the screen.  Tapping each icon results in a specific function.

For example, tapping the red dice generates a random fraction.  Denominators range from 1 to 12.  Once the denominator is set, numerators can be any number that results in a proper fraction.


When the question mark is tapped, a question is generated and displayed on a moveable note.  To answer the question students drag number tiles to make the fraction.  Usually it is best to start with the denominator.  If using this app in a classroom, the teacher should explain that the denominator represents the number of equal parts.  For this example, the student would first slide the three tile to the denominator position.  Next, the student should slide a one to the numerator position.  Once the numerator and denominator have been properly set, the students should tap the check mark.  When this icon is tapped the app compares the students answer to the correct answer for the question.


A scoreboard displays student progress as they work with the app.  It shows the topic, number of questions attempted and the percent correct.  Quiz questions are based on three main topic areas:

• Naming Fractions

• Equivalent Fractions

• Comparing Fractions

Various other functions are performed when other icons are tapped.  This chart explains the other functions.notebook

I hope that teachers will let me know if they are interested in evaluating this app for use at their school.   I have a limited number of download codes for FREE evaluation copies of this app.   For some students learning about fractions is difficult.  It is my hope that this colorful interactive app will help them in their journey to master fraction concepts.


Save the Galaxy!

I guess I am on a monsters kick lately.  My latest strategy game involves monsters that have invaded the galaxy.  Your job is to use logical thinking skills to save the galaxy!


To solve the puzzle the player must swipe in the direction that they wish the monster to move.  The app is available for both iOS and Apple TV.  On an iPad the player swipes the screen to specify the direction.  If you are playing on an Apple TV either the Siri remote or a bluetooth compatible game controller can be used.


The galaxy is divided into 20 sectors so there are 20 puzzles in the app.  The app has a 3-D look to it and animation adds to the effect that you are traveling through space.  As you might of guessed I am a StarTrek fan doing an app with a space theme was fun for me.

I hope you enjoy playing Space Monsters! Save the Galaxy. A limited number of free promotional codes are available by request.  The app is offered exclusively by the iTunes App Store and sells for $0.99.  Please visit our website for more information about this and other apps for education.

Just in Time for Halloween

What could be more fun that having your monster be chased by three other monsters?  Well that’s the theme of my latest math game.title

Ziggy, Spot and Pete are the three monsters that you want to avoid.  Harry is your monster and is controlled by tapping arrows on the iPad version or swiping the Siri Remote on the tvOS version.  The tvOS version also supports the use of a game controller so Harry can be moved using a compatible gaming device.


The object of the game is to move Harry to the correct answer for a math problem shown at the bottom of the screen.  Anytime that  Ziggy, Spot or Pete run into Harry as they bounce around the screen, Harry loses a unit of energy.  Fortunately when Harry gets an answer correct he gets a unit of energy back.  The goal is to score ten points before running out of energy.



Teachers and parents will like the wide range of problems.  Problems are randomly generated so the game is different every time it is played.  Skills are organized and defined using the Common Core Standards.  Look Out! Monsters! is a fast-paced game specifically designed to help kids get quicker at doing mental arithmetic.  A limited number of free promotional codes are available by request.  The app is offered exclusively by the iTunes App Store and sells for $0.99.  Please visit our website for more information about this and other apps for education.

Skills Chart

Operations and Algebraic Thinking Add within 20 Integers from 1 to 10 
Operations and Algebraic Thinking Add within 20. Integers from 5 to 20
Operations and Algebraic Thinking Add within 20. Integers from 10 to 20
Operations and Algebraic Thinking Add within 20. Integers from 1 to 20 
Operations and Algebraic Thinking Subtract within 20. Integers from 1 to 10
Operations and Algebraic Thinking Subtract within 20. Integers from 1 to 20 
Operations and Algebraic Thinking Determine the unknown whole number in an addition equation. Integers from 1 to 20
Numbers and Operations in Base Ten Add within 100, including adding a two-digit number and a one-digit number. Integers from 1 to 100 and 1 to 10
Numbers and Operations in Base Ten Given a two digit number mentally find 10 more or 10 less. Integers from 10 to 100 and 10
Numbers and Operations in Base Ten Subtract multiples of 10 in the range 10-90 from multiples of 10 in the range 10-90 (positive or zero differences) Integers from 10 to 90
Operations and Algebraic Thinking Fluently add and subtract within 20 using mental strategies. Integers from 0 to 20
Numbers and Operations in Base Ten Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction. Integers from 0 to 100
Numbers and Operations in Base Ten Add up to four two-digit numbers using strategies based on place value and properties of operations. Number Range: Integers from 0 to 1000
Numbers and Operations in Base Ten Mentally add 10 or 100 to a given number 100–900, and mentally subtract 10 or 100 from a given number 100–900. Number Range: Integers from 10 to 100 and 100 to 900
Operations and Algebraic Thinking Fluently multiply within 100. Factors from 0 to 10
Operations and Algebraic Thinking Fluently divide within 100. Divisors and Quotients from 0 to 10
Number and Operations in Base Ten Recognize that in a multi-digit whole number, a digit in one place represents ten times what it represents in the place to its right. Dividends from 10 to 1000 and Divisors of 10 or 100
Operations and Algebraic Thinking Use parentheses, brackets, or braces in numerical expressions, and evaluate expressions with these symbols. Integers 1 to 10
Expressions and Equations Evaluate expressions at specific values of their variables. Integers 1 to 10
Expressions and Equations Solve real-world and mathematical problems by writing and solving equations of the form x + p = q and px = q for cases in which p, q and x are all nonnegative rational numbers. Integers 1 to 10


Classroom Spinners


Teachers need lots of tools in their arsenal when it comes to teaching any subject, especially math.  The use of a spinner is a great way to introduce math concepts related to probability.  The Classroom Spinners app provides teachers with six different types of spinners that can be configured to have sections with color or no color.  The sections can be labelled with numbers or letter.  The sections can also be unlabelled.

Tapping the info button brings up a screen explaining the various functions of the app.


The Classroom Spinners screen shown below is configured to have six sections.  Each section has a different color and the sections are labelled with letters.  Many different investigations of probability theory can be explored using this setup.


For example, here are a few questions to ask the students:

  1.  What is the probability of landing on a vowel?
  2. What is the probability of landing on A,B, or C?
  3. If the last five spins were A,A,C,A,A, what is the probability of the next spin being the letter A?
  4. What is the probability of getting an B on the first spin and E on the second?
  5. If you spin 10 times about how many times would you expect the letter D to occur?

Tapping the sigma icon will display a table of the Experimental Outcomes:


In this experiment the letter C was randomly selected 4 times.  The Theoretical Probability for any given letter is 16.7%.  What do you think will happen to the Experimental Outcome for the letter C if 90 more spins are performed?  Theoretically, how many times will C occur if  the experiment is run 1,000 times?

Classroom Spinners is a useful tool for teachers to have in their tool bag.   Check it out and let me know what you think.







Star Maze

Star Maze extends my series of visual problem solving challenges and is for iOS and tvOS devices.  Like Slip Sliders, Critter MatesThe Bird Puzzle, The Menagerie and The Hungry Rat, Star Maze is based on a grid where the object is to control a character’s movement to solve a visual challenge.  In Star Maze the characters position can be switched with a blocker and this feature is critical to solving some of the puzzles.  The character can move in any of the four directions, left, down, right or up but only stops when it encounters a wall or a target (star).


Working to solve the Star Maze puzzles helps to develop logical thinking skills because the sequence in which the moves are made effects how many moves it takes to solve the puzzle.  The goal is to collect all of the stars in the least number of moves.  Star Maze differs from Slip Sliders because in Star Maze the character can switch positions with a blocker.  A blocker is a fixed wall in the maze that can only be moved by changing positions with the character.   In the screen shot show above the owl is the character and the black square is the blocker.


Obviously by moving the owl straight up you can capture the first star, but now what?  Moving right and down doesn’t help much, but what about switching the character and the blocker.  Tap the switch icon and now the puzzle board looks like this:


Now by moving straight up again, another star can be captured.

Solving the Star Maze puzzles can be fun and relaxing.  There is an Apple TV version so you can play Star Maze on your big screen TV with the whole family in the comfort of your living room. Star Maze is also available for iOS devices in the iPad family.  Try it out and let me know what you think?

If you like puzzles you might like Star Maze.   For $0.99 you get the iPad and Apple TV versions.  For more information about the Star Maze app, please visit our website. The app is available at iTunes.

Slip Sliders

Slip Sliders is the latest in my series of visual puzzles for iOS and tvOS devices.  Slip Sliders joins Critter Mates, The Bird Puzzle, The Menagerie and The Hungry Rat as visual puzzles designed to help develop logical thinking skills.

I’ve always enjoyed puzzles and so having the opportunity to design them is particularly rewarding.  For Slip Sliders, I needed a set of icons that could be paired up as part of solving the puzzle. Using Adobe Illustrator and Photoshop I created a set of birds.  It works great to draw the images large (512px x 512px) and then shrink them to the size of the icons.  By the way, I liked the birds so much I made a couple of coffee cups using the images.  The icons slide based on a particular set of rules.  They move in the one direction (left, down, right or up) until they hit an obstacle.  One of the tricky parts about solving the Slip Sliders’ puzzles is that sometimes you will need to create the obstacles in order to be able to change the direction that the slider can move.

Initially the puzzles are fairly simple and a solution can be achieved with just a few moves. Show below is how the first puzzle looks on an Apple TV.  Obviously the solution is simple, just move each of the birds on the left to the right and they will find a mate.  The birds on the left are sliders and therefore they can be moved.  The birds on the right stay in a fixed position and are the targets.

Slip Sliders Screen 1

In the second puzzle things get a little more difficult.  The birds cannot just simply be moved down because the first two need to switch columns.  I like this type of problem because the are multiple solutions.  If you are a teacher and use problems like this with your students you will find that one benefit is that several students can share different answers and it is not just the first student who finds a solution that gets the reinforcement.

Slip Sliders Screen 2.png

As you progress through the puzzles by tapping the right arrow, the puzzles get even more challenging.  For example, in the puzzles shown below from an iPad screen, how are you going to get the slider to stop on the red bird show in approximately the middle of the screen?

Slip Sliders Screen 3

If you like puzzles you might like Slip Sliders.   For $0.99 you get the iPad and Apple TV versions.  For more information about the Slip Sliders app, please visit our website. The app is available at iTunes.


Line Design (a.k.a. String Art)

In general, one of my goals in designing the Hands-On Math apps was to create ways to simulate learning experiences that students would have if using actual manipulatives.  Simulated manipulatives can offer additional learning opportunities.


Special features, in the Line Design app, take the learning opportunities beyond what can be down with physical manipulates.  For example, a grid with the x and y axes labelled can be added to the image.


Line Design can be used for exploring the relationship between geometry and art.  In addition to calling line designs, string art, sometimes it is referred to as aesthenometry, Using the term, aesthenometry, refers more to the aesthetic beauty of the designs.


It is always fun for students to use boards, nails and various colors of embroidery thread to make string artworks to hang on their wall.  The process involves lots of careful planning, measuring and some materials (boards, nails and string).  The Line Design app can be used to plan the project and to provide help in choosing the colors and design patterns to be used.

Personally my favorite pattern to use for instructional purposes is the circle.  When the circle design is selected a slider appears.  Using the slider the number of points on the circle can be set to any number between 3 and 36.


There are lots of mathematically interesting explorations that are available in this mode.  Here are a couple of suggestions:

  1. With the number of points set to 12, what shape will result if lines are draw to connect every other point?
  2. What shape results when the number of points is set to 10 and every other point is connected.  What about connecting every fourth point.
  3. What’s the difference between setting the number of points to a prime number versus a composite number?
  4. Set the number of points to 24.  Explore connecting every 4, 6, or 8 point.

The learning environment gets even richer if the circular protractor is added to the iPad display.  In this mode students can measure angles. Here we have the number of points set to 36.  The screen shows a 30° angle.  Two legs of the triangle are radii of the same circle and therefore congruent.  What is the measure of the other two angles?