Evaluation of Khan Academy Course using CARP

Selection and Overall Impression I truly enjoy the Khan Academy eLearning’s and have used them myself when I was retaking calculus a couple of years ago. They are an excellent example of how to connect with learners in an engaging way. I chose to review the Khan Academy video for “Meet the Heart!”. The video is ten minutes in length and narrated by Rishi Desai, a pediatric infectious disease physician. “Meet the Heart!” is the first module in a course for an introduction to the circulatory system. The full course includes 10 modules.

Nine of the modules are videos and one is text. There are three practice quizzes to be completed to complete the full module. It is difficult to state the exact audience for this content but from my experience teaching children and adults I would estimate that the content target audience is anyone studying the circulatory system that is 14 years old and older.

My initial impression of the eLearning was good based on several aspects that correlate to much of the visual design and accessibility standards we have been studying. The course itself offers many options for the learner. There is a transcript of the content as well as closed captioning of Dr. Desai’s explanation. It was easy to navigate the course through the video tools as well as the navigation pane on the left-hand side of the screen where the learner could access any of the modules directly and could navigate back to a module to repeat the information. There were links to share the content in Google classroom as well as on social media sites like Facebook and Twitter.

Evaluating the content using CARP Contrast

The video has a solid black background throughout allowing for the contrast of the picture (which is in color) to stand out against the background. The contrast between the image and the solid black background holds the learner’s attention on the image as the doctor is discussing the heart. As the video progresses annotations appear as both images and test. The annotations are in color aligning with the area of anatomy around the heart to help explain the pulmonary system. The annotations are drawings of the lungs in blue (indicating breath or air) and the diaphragm in red (indicating muscle). The entire section of the area shown (rib cage, heart, lungs, diaphragm) is annotated in a third contrasting color (green) to note the section is called the thorax. “One of the goals of designing learning and informational materials is to reduce the cognitive effort required to understand them� (Malamed, 2015. P. 136). Each of these contrasts within the drawings and text help the learner to gain a greater understanding of the content. As the video progresses, we see additional annotations focused around an enlarged image of the heart. Each drawing that is made is annotated with text in the same color creating contrast separating out each description. The learner can easily ascertain which text belongs to which drawing based on the contrasting colors.

Figure 1: Initial screen showing the heart and rib cage

Figure 2: Showing the lungs and diaphragm in contrasting color

Figure 3: Thorax region (heart, lungs, diaphragm) indicated in green

Alignment As noted above the information that is being presented is centered on the page initially and no extraneous text or images distract the learner from focusing on the content. As the video progresses the annotations remain centered on the image organizing the information within the context of the anatomical position of the pulmonary system. “Alignment provides visual order by creating implied vertical or horizontal lines along the edges� (Malamed, 2015, p. 59). The drawing in the video align with the human anatomy on a vertical and horizontal access making the drawing easy to understand.

The alignment of the closed captioning text at the bottom of the screen does not interfere with the content discussed and annotated. As we move to the next section of the video where the doctor is more specifically discussing pulmonary and systemic circulatory systems, the video centers directly on the heart. The heart is centered on the screen and the annotations are drawn larger but remain in

alignment with the image. As the information becomes more detailed the need to create alignment to the text is accomplished through arrows or other shapes aligned with the corresponding text in the same color. Even though the drawings are rudimentary they alignment of the objects connects the learner to their location in the human body effectively.

Repetition The repetition in the video is done specifically to reinforce the concepts. The drawings in the first section of the video are repeated and expanded upon as the video progresses. We see a larger image of the heart with the thorax area redrawn in the same contrasting colors. “Repetition creates a rhythm – a sense of visual motion – that establishes a unified look” (Malamed, 2015, p. 174). The repetition of the image and the annotated drawings unifies the content being discussed. The repeated use of arrows to show both direction (flow) and connection (the specific text with the anatomical area), increases the learners understanding of the visual image. Repetition of color – blue for air (lungs); red for blood/muscle (flow); white for specific areas of the heart and their purpose (waste, oxygen, nutrients) is an effective tool for reinforcing the concepts of systemic and pulmonary flow.

Figure 4: Enlarged image of the heart annotated to explain systemic flow

Figure 5: Enlarged image of the heart annotated to explain pulmonary flow

Proximity “Visual grouping is one of the most powerful techniques a designer can use to communicate. It lets learner know what elements in a visual are related to each other” (Malamed, 2015, p. 197). The video with annotations in this eLearning uses proximity in an incredibly effective manner. Each of the components being drawn is set in proximity to the heart as it is within the human body. The diagram of the heart itself is large enough to see the different areas being discussed and the use of arrows demonstrate the proximity of the areas of the heart to each other as well as the flow explaining how each cell can take in nutrients and express waste efficiently. There can be no mistake of how the heart is interacting with the body through systemic and pulmonary flow.

What could be improved Although I love the bit of fun being injected into the video by describing a “toe cell” I felt it was unnecessary to the visual design to suddenly have a square drawn representing the toe. It distracted from the content. It would have been a better visual representation to just draw a rudimentary cell using the same color contrasts being used previously. The image with the annotations began to devolve the alignment that was established earlier in the video. My suggestion is to change the image of the heart to show the areas as noted in Figure 6. The drawings toward the end of the video became a bit distracting and didn’t allow the learner to focus on the content as much as watching the creator draw on the screen. With the closed captioning at the bottom of the screen the video loses the value established earlier with proximity rather than clarifying the content. Overall the contrast of color was executed well but the blue on black background is considered a poor color contrast. When drawing text there is a risk

of legibility and as the creator increased the amount of text on the screen the original benefits of the alignment and proximity began to lose effectiveness.

Figure 6: Suggestion on how the heart image could be improved

Figure 7: Suggestion on cell image rather than "toe" cell

References Malamed, C. (2015). Visual design solutions: Principles and creative inspiration for learning professionals.

Hoboken, NJ: Wiley.

Desai, R. (2012). Meet the heart! (video). Retrieved July 26, 2020, from https://www.khanacademy.org/science/health-and-medicine/human-anatomy-andphysiology/heart-introduction/v/meet-the-heart