The “lessons” below could also be described as animations or even as slide shows. In fact, we are not exactly sure what to call them! They illustrate concepts and steps required to carry out different operations. They have audio commentary although they can be viewed with just the text. The lessons developed so far include six on fractions, three on percent, and one on long division.
The links below will open the lessons in a new window. There is a navigation bar at the bottom each lesson that will allow you to:
 Pause and play the lesson
 Skip through different sections
 Switch the audio on and off
 View the lesson in fullscreen mode
 See thumbnails of each screen and skip around the lesson
We would really like to hear what you think about these lessons. We will use what we learn to make them better.
Fractions Lessons
#1: Introducing Fractions (2:42 min.) This lesson introduces the concept of fractions as being part of one whole unit. It illustrates how numerators and denominators are used when writing and saying fractions. 

#2: Equivalent Fractions (3:41 min.) The concept of equivalency of fractions is explored with examples of finding equivalent fractions by multiplying and dividing the numerator and denominator by the same number. 

#3: Common Denominators (4:10 min.) The need for and use of common denominators are discussed in this brief lesson. Guidance on how to find common denominators using least common multiples is shown. 

#4: Adding and Subtracting Fractions (3:46 min.) Examples are illustrated showing how to add and how to subtract fractions. These include adding and subtracting fractions with both the same denominator and with different denominators. 

#5: Simplifying Fractions (3:12 min.) Two different methods of how to simplify fractions are shown. One involves dividing the numerator and denominator by their greatest common factor. The other uses more of a “keep dividing until you can’t divide anymore” method. 

#6: Mixed Numbers and Improper Fractions (4:12 min.) The final lesson in the series covers when to use mixed numbers and when to use improper fractions. It shows the steps to convert between both formats. 
You will also find more textbased guidance on how to work with fractions here. There are also a number of fraction worksheets as well as some fraction games.
Percent Lessons
#1: Introduction This lesson looks at the concept of percent and illustrates the importance of the number 100 in any percent calculation. 

#2: Calculating with Percent e.g. 40% of 150 is ? The first of three exercise types is covered in this lesson. It shows how the part can be found given the percent and the whole amount. e.g. what is 60% of 80? 

#3: Calculating with Percent e.g. 12 out of 20 is what % & 80 is 12% of ? Two exercise types are covered in this lesson; finding the percent when the part and whole are known and finding the whole amount when the part and percent are known. As in lesson 2, this is illustrated using a double number line. 
You will find more here on calculating with percent. There are also a number of printable worksheets here that can be used for practice.
Division Lessons
Long Division: Stepbystep A stepbystep animation showing long division as sharing alongside the algorithmic calculation steps. 
There is a long division worksheet generator here that provides limitless questions to practice the steps shown in the minilesson above.