The Effectiveness of Khan Academy Videos on Elementary Math Instruction: A Quantitative Study Proposal
This proposal aims to test the effectiveness of Khan Academy videos in a fourth grade Common Core Standard math unit teaching fractions (CCSS.Math.Content.4.NF Number and OperationsFractions) in the Franklin Township school district in Somerset, NJ. Half the fourth grade classrooms will use Khan Academy videos in addition to the Common Core instruction mandated by the district. A district wide test will provide the quantitative data for the Khan and control groups. Qualitative data will be gathered from the Khan group through a survey given at the end of the unit. The results should further research in education, instructional videos and learning applications.
Jessica Lucas December 2014
The Effectiveness of Khan Academy Videos on Elementary Math Instruction
Introduction Due to this century’s growing global connectivity, instructional videos have become an important tool for all kinds of learning. One popular example is the Khan Academy. Started eight years ago by Sal Khan, it is a free collection of short instructional videos, mostly aimed at teaching math and science concepts to students pre-kindergarten all the way to university levels. Students all over the world are using these videos to learn new skills and enhance their education. However, there has been little research into whether these videos are actually helping students learn the material.
What Makes a Good Instructional Video? In order to determine whether the Khan Academy videos are truly effective tool in learning, we must first examine the research as to what makes a good instructional video and do the Khan Academy videos meet that criteria. The research on what makes a good instructional video is diverse and is generally based on insights found in the cognitive theory of multimedia learning (CTML) which blends an understanding of how our brains process and understand information with the multimedia methods with which we present information (Mayer, 2014). Dual code theory, a construct under CTML, is the idea that audio and visual information is processed by learners at the same time (Mayer, 2014). Instructional videos inherently implement dual coding theory. When creating instructional videos, designers need to pay attention to cognitive load. The redundancy effect is visual text on a screen that duplicates the audio portion, increasing cognitive load and lowering learning outcomes (Mayer, Heiser & Lonn, 2001). Recent quantitative studies have shown that germane cognitive load or deep learning is induced when an abridged version of the audio portion is show with the visual portion (i.e. important phrases in the frame) (Yue et al., 2013) (Mayer & Johnson, 2008). Two important design implications evolved from this research: one, on-screen text should consist of short keywords or phrases from the narrative and two, the text should be placed near the relevant image (Mayer & Johnson, 2008). In addition to designing to reduce cognitive load, Swarts (2012) suggests some of the following design features for “good” instructional videos: LUCAS 2
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Use headings and text to alert the viewer to the structure of the content - Also known as the signaling principle, this give the viewer a context for the information.
Use redundancy effectively – Swarts suggests using call outs or camera techniques, such as zoom or pause to highlight important concepts or actions.
Seduce the viewer – Swarts argues that good videos “make a big promise of something to be learned or accomplished, proceed incrementally by making and fulfilling small promises along the way, and then make good on the larger promise” (2012).
Don’t ignore good production value - In addition Swarts says we should not forget to create videos with. HD quality, proper timing, good editing tool use, etc. (2012)
Van der Meij et al., also has guidelines for instructional videos (2013). They focused on synthesizing instruction design theories, including CTML and minimalism, as well as other recommendations from existing research into eight guidelines for the design of instructional videos, particularly as it pertains to software training. In academia, instructional videos are also being used to replace some classroom lectures. Hibbert (2014) studied the effectiveness of online videos used in the School of Continuing Education at Columbia University and concluded that the use of audio/visual element, high-quality production and a short four-minute view is optimal for academic lecture videos. Research in minimalism and instructional videos suggest similar recommendations (Pflugfelder, 2013).
Most of these general guidelines and cognitive implications for instructional videos are used in Khan Academy videos. In a video by Khan Academy creator Sal Khan, he highlights the four main tips for creating videos in the style of the Khan Academy (Kamenetz, 2013). Points include keeping the talk conversational, not reading from a script, using simple visuals and colors, and limiting the video to under ten minutes. Khan suggests chunking – breaking up information into smaller segments- for concepts that may need more than ten minutes (Kamenetz, 2013).
Most of these popular Khan-style tips seem to conform to the principles of CTML but have yet to be empirically tested as such. In one study that does use Khan-style videos, Barreto et al. (2014) tested three classes in a university biochemistry course to determine whether an ‘inverted’ classroom technique resulted in better scores. The inverted classroom, also known as a flipped LUCAS 3
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classroom, consisted of emailing the students links to ‘Khan-style’ videos, replacing the traditional lecture, and then group problem solving within the classroom. After taking the final test, students were asked to complete a Likert-type survey – the first question “the videos were useful in preparing students for the test”, was used to validate the hypothesis. The results indicated that the videos had a positive effect on student performance (Barreto et al., 2014), however true quantitative studies into the effectiveness of Khan-style videos remain untapped.
Gaps in the Research The Barreto et al study of the effectiveness of Khan-style videos examined university students in high-level biochemistry course (2014). The results indicated that the videos has a positive effect, but the study was limited in that the participating students were already operating at an advanced level of mathematics and also, by the declaration of their major, interested and inclined toward the subject matter. The results were also based on self-reporting and not a reflection of actual high test scores.
In a study of younger students, Light & Pierson examined the use of the Khan Academy in eighteen Chilean K – 12 classrooms (2014). Taking an ethnographical approach, the researchers observed and interviewed teachers and students to understand how the Khan Academy was being used. The instructional videos however were largely unused by the class. The researchers concluded there were several factors involved including low connectivity and lack of Spanish subtitles (Light & Pierson, 2014).
This proposed research study will quantify and qualify the effectiveness Khan Academy instructional videos with an elementary level population, specifically fourth grade math instruction. The study aims to answer the following questions: 1) Does viewing the Khan Academy videos in addition to district mandated instruction result in higher scores on district tests? 2) Does gender make difference? 3) What element of the videos are perceived to be most helpful? 4) Does this correlate with existing recommendations for instructional video design?
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Research Methods The research will take place at the six elementary schools within the Franklin Township school district in Somerset, NJ. With many fourth grade classrooms ranging in size from 18 to 24 students and a diverse student population, the district offers a large sample size for this research study. Common Core Standard The Franklin Township school district, like most public schools in the state of New Jersey, follows the Common Core Standard of instruction. The instructional videos found at the Khan Academy website correlate directly with the Common Core Standard (as mapped in Appendix A), ensuring that the material presented in the videos will be the same as that in the classroom. The purpose of this study is to determine what effect, if any, the addition of Khan Academy videos has on student performance, and is not a study of the Common Core Standard. Running the Study Franklin Township School District currently issues district wide tests in math to assess the progress of their students. This is for district’s purposes and does not affect the student’s actual grades within the classroom or has anything directly to do with the New Jersey state testing done on elementary students. As these tests are given to all students within the district, they can also be used for the quantitative portion of the study data.
The proposed study will take place during the course of a full math instructional unit within a single marking period. For purposes of the study, each fourth grade classroom in all six elementary schools will be assigned to either the control group or the Khan group.
The math unit used for this study will be the unit on fractions (CCSS.Math.Content.4.NF Number and Operations-Fractions). The control group will receive the math unit’s instruction as per district mandate using the Common Core Standard. The Khan group will receive the exact same instruction with the following addition: Students will view the Common Core Standard corresponding Khan Academy videos prior to the lesson (see Appendix A). LUCAS 5
The Effectiveness of Khan Academy Videos on Elementary Math Instruction Franklin Township NJ Fourth Grade Classes [Estimated]
Elementary School
Control Group
Khan Group
Total
Conerly Road
56
63
119
Elizabeth Avenue
44
43
87
Franklin Park
62
61
123
Hillcrest
35
38
73
MacAfee Road
43
47
90
Pine Grove Manor
38
36
74
278
288
566
Total Source: Estimated
While is it possible for students to view the videos multiple times on their own, all students in the Khan group will see the video at least once prior to the lesson. Whether students from the Control group view the Khan videos on their own cannot be controlled by this study, nor do we feel it is relevant to the overall outcome. The study is testing whether the Khan videos appear to have an effect across a large sample size, not individual students.
The individual classroom teacher will ultimately determine how to incorporate the videos. However, the teachers will receive a training session at the beginning of the study informing them that the videos (as mapped in Appendix A) should be shown prior to the instructor-led lesson on each micro topic. For further discussion on the individual role of the teacher, see Assumptions and Considerations. At the end of the unit, the district test will be given to all students in both the Khan and control group. The study will require one question to be added – Are you a boy or girl? - to the end the district test for demographic purposes. After taking the district test, students in the Khan group will be given a survey to assess their perception of the videos. (See Appendix B for survey questions).
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Study Time Line The timeline of the study is determined by the length of the fractions math unit in the fourth grade classrooms. Once the district tests are graded, the generation and analysis of the data should take two weeks.
Teacher Pre-Training Before beginning the unit, Khan classroom teachers will attend a short meeting explaining the project and the general instructions for using the videos within the classroom. Using the chart in Appendix A, they can match the Common Core Standard with a Khan Academy video that covers the same material. Teachers should show the corresponding video(s) prior to the classroom instruction. For example, when teaching the equivalent fractions micro unit (CCSS.Math.Content.4.NF.A.1), the classroom teacher might use the following approach: 1) Show Khan Academy videos Intro to equivalent fractions and Visualizing equivalent fractions. 2) Begin classroom lesson on equivalent fractions. 3) Small group work. 4) Show Khan Academy video Equivalent fraction word problem example 1. 5) Classroom instruction on fraction word problems. 6) Show Khan Academy video Equivalent fraction word problem example 2. 7) Individual work on word problems. The Khan Academy video titles should appear on each teacher’s lesson plan that is submitted to the administration so that the researchers can ensure that the videos are being used as directed.
Analysis Plan The completed and graded tests will be coded by the researchers for the following: Gender Group Score (number of correct answers)
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An analysis of the data will include calculations for mean and standard deviation for each group and then again for gender and group. The following tables illustrate the resulting data. Quantitative Data for Khan and Control Groups [Estimated]
Group Sample Size (n)
Control 278
Khan 288
Mean Score Standard Deviation
The literature on instructional videos and the studies focusing on Khan Academy videos did not examine gender as a variable. Since this study will generate data that can be analyzed for gender, we will do so as follows: Quantitative Data for Khan and Control Groups, Separated for Gender
Group Gender
Control Female
Male
Khan Female
Male
Sample Size (n) Mean Score Standard Deviation
The completed surveys will be analyzed in a similar fashion as the test data. Question 1 determines gender and Question 4 – Did you watch any of the videos at home? – may be used when discussing the implications of the test data. Questions 2 and 3 directly address the purposes of this study. The last two open ended questions will be reviewed and coded for similar ideas and topics. These questions will be used to determine what elements of the video were perceived as most useful. The full survey is found in Appendix B. Assumptions and Considerations The Khan Academy is a website with free access to the instructional videos used in this study. Therefore, there is no cost to the school district to access and show the videos. However, the district will have to ensure that all Khan classrooms are equipped with a laptop computer with LUCAS 8
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internet access and the ability to connect to an overhead projector. As most classrooms in the district are already equipped with these basic tools, the hardware cost should be minimal.
Although the main singular variable in the study is the addition of the Khan videos at specific times within the district’s mandated instruction, we are still somewhat dependent on the individual teacher’s judgment as to when the Khan videos are shown within the district mandated curriculum. As students in most American public schools are taught in classrooms by individual instructors, this is a commonality across the educational system as a whole and therefore the slightly different teaching styles of individual instructors is a constant. It is true that some teachers may integrate the videos into the lesson more effectively than other teachers, however that is also true of all learning in general. Franklin Township is a very large district and the large sample size should mitigate some of these concerns, as well the pre-training that Khan classroom teachers will receive that the beginning of the unit. Ethical Concerns and Considerations This study is dealing with an underage population and factors that could possibly affect the students’ ability to learn the material in a negative manner need to be addressed. As the study is only adding a small instructional change to a single math unit, one that is in addition to and not taking away from the district mandated curriculum, we feel that the possible negative effects are small compared to the potentially positive effects on learning. Many studies support the general effectiveness of the instructional video as a learning tool (Barreto et al., 2014) (Hibbert, 2014) (Yue et al., 2013) (Mayer & Johnson, 2008).
Conclusion Instructional videos are an ongoing part of twenty-first century life and integral part of education. As one of the more popular educational sites, the Khan Academy offers instructional videos to a global audience. This study hopes to quantitatively test the effectiveness of these videos in the classroom. As the data of this study will be also be parsed by gender, the results could provide further insight into the ways in which gender affects how students respond to instructional videos. The results of this study may help future researchers develop effective learning programs and instructional videos.
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References Andrade, Jeanette, Wen-Hao David Huang, and Dawn M. Bohn. "Multimedia's Effect on College Students' Quantitative Mental Effort Scores and Qualitative Extraneous Cognitive Load Responses in a Food Science and Human Nutrition Course." Journal Of Food Science Education 13, no. 3 (July 2014): 40. Barreto, Jose, et al. "A Case Study for Teaching Quantitative Biochemical Buffer Problems Using Group Work and "Khan Style" Videos." Journal Of College Science Teaching 44, no. 1 (September 2014): 34-39. Hibbert, Melaine “What Makes an Online Instructional Video Compelling?” EDUCAUSE Review Online, published April 7, 2014. Accessed October 5, 2014. (http://www.educause.edu/ero/article/what-makes-online-instructional-video-compelling) Hye Won, Jang, and Kim Kyong-Jee. "Use of online clinical videos for clinical skills training for medical students: benefits and challenges." BMC Medical Education 14, no. 1 (May 2014) Kamenetz, Anya. “4 Tips for Creating a Sal Khan Style-Instruction Video… From Sal Khan.” FastCompany.com, published March 13, 2013. Accessed October 7, 2014. (http://www.fastcompany.com/3007137/industries-watch/4-tips-creating-sal-khan-styleinstruction-videofrom-sal-khan) Light, Daniel, and Elizabeth Pierson. 2014. "Increasing Student Engagement in Math: The Use of Khan Academy in Chilean Classrooms." International Journal Of Education & Development Using Information & Communication Technology 10, no. 2: 103-119. Mayer, Richard, ed. The Cambridge Handbook of Multimedia Learning. New York, NY: Cambridge University Press 2005, second ed. 2014; 43-71. Mayer, R. E., Heiser, J., & Lonn, S. (2001). “Cognitive constraints on multimedia learning: When presenting more material results in less understanding.” Journal Of Educational Psychology, 93(1), 187-198. Mayer, R. E., & Moreno, R. (2003). Nine Ways to Reduce Cognitive Load in Multimedia Learning. Educational Psychologist, 38(1), 43-52. Mayer, Richard E., and Cheryl I. Johnson. 2008. "Revising the redundancy principle in multimedia learning." Journal Of Educational Psychology 100, no. 2: 380-386. Morain, M., and J. Swarts. "Yoututorial: A framework for assessing instructional online video." Technical Communication Quarterly 21, no. 1 (January 1, 2012): 6-24. Peters, Dorian. “Interface Design for Learning: Design Strategies for Learning Experiences,” UXmatters.com, published August 4, 2014. Accessed October 7, 2014. (http://www.uxmatters.com/mt/archives/2014/08/interface-design-for-learning-design-strategiesfor-learning-experiences.php#sthash.9hNletY7.dpuf) LUCAS 10
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Pflugfelder, Ehren Helmut. "The Minimalist Approach to Online Instructional Videos." Technical Communication 60, no. 2 (May 2013): 131-146. Swarts, J. "New modes of help: Best practices for instructional video." Technical Communication 59, no. 3 (August 1, 2012): 195-206. van der Meij, Hans, and Jan van der Meij. "Eight Guidelines for the Design of Instructional Videos for Software Training." Technical Communication 60, no. 3 (August 2013): 205-228. Yue, Carole L., Elizabeth Ligon Bjork, and Robert A. Bjork. 2013. "Reducing verbal redundancy in multimedia learning: An undesired desirable difficulty?." Journal Of Educational Psychology 105, no. 2: 266-277. Yue, Carole, Jessie Kim, Rikke Ogawa, Elena Stark, and Sara Kim. 2013. "Applying the cognitive theory of multimedia learning: an analysis of medical animations." Medical Education 47, no. 4: 375-387.
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Appendix A We mapped the common core standards to the corresponding Khan Academy videos in the following table. This table is to be used by the Khan classroom teachers to incorporate the videos into their lesson plans. Sources: Common Core Standard - http://www.ixl.com/standards/common-core/math/grade-4 Khan Academy Videos - http://www.khanacademy.org/math/cc-fourth-grade-math/cc-4th-fractions-topic
Common Core Standard
Khan Academy Videos
CCSS.Math.Content.4 Extend understanding of fraction equivalence and ordering. CCSS.Math.Content.4.NF.A.1 Explain why a fraction a/b is
Intro to equivalent fractions
equivalent to a fraction (n × a)/(n × b) by using visual fraction models, with attention to how the number and size of the parts differ even though the two fractions themselves
Visualizing equivalent fractions Equivalent fraction word problem example
are the same size. Use this principle to recognize and generate equivalent fractions.
Equivalent fractions
Patterns of equivalent fractions
Reduce fractions to lowest terms
Equivalent fraction word problem example 2 Equivalent fraction word problem example 3 More on equivalent fractions Equivalent fraction word problem example 4 Equivalent fractions
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Common Core Standard CCSS.Math.Content.4.NF.A.2 Compare two fractions with
Khan Academy Videos Comparing fractions with different denominators
different numerators and different denominators, e.g., by creating common denominators or numerators, or by
Comparing fractions with different numerators and
comparing to a benchmark fraction such as 1/2. Recognize
denominators
that comparisons are valid only when the two fractions refer
Comparing and ordering fractions
to the same whole. Record the results of comparisons with symbols >, =, or <, and justify the conclusions, e.g., by
Ordering fractions
using a visual fraction model.
Benchmark fractions
Compare fractions using benchmarks
Compare fractions using models
Compare fractions
Order fractions
Compare sums and differences of fractions
CCSS.Math.Content.4 Build fractions from unit fractions by applying and extending previous understandings of operations on whole numbers. CCSS.Math.Content.4.NF.B.3a Understand addition and
Adding fractions with like denominators
subtraction of fractions as joining and separating parts referring to the same whole.
Add and subtract fractions with like denominators using number lines
Add and subtract fractions with like denominators)
Compare sums and differences of fractions with like
Adding fractions with common denominators Subtracting fractions with like denominators Subtracting fractions with common denominators
denominators
Add 3 or more fractions with like denominators
Compare sums of unit fractions
Compare differences of unit fractions
Compare sums and differences of unit fractions
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Common Core Standard CCSS.Math.Content.4.NF.B.3b Decompose a fraction into
Khan Academy Videos Decomposing a fraction visually
a sum of fractions with the same denominator in more than one way, recording each decomposition by an equation. Justify decompositions, e.g., by using a visual fraction
Decomposing a mixed number Adding up fractions
model. Decomposing fraction
Decompose fractions into unit fractions
Decompose fractions
Decompose fractions multiple ways
Add and subtract fractions with like denominators
Add 3 or more fractions with like denominators
CCSS.Math.Content.4.NF.B.3c Add and subtract mixed
Mixed numbers: changing to improper fractions
numbers with like denominators, e.g., by replacing each mixed number with an equivalent fraction, and/or by using properties of operations and the relationship between addition and subtraction.
Add and subtract mixed numbers with like denominators
Mixed numbers: changing from an improper fraction Converting mixed numbers and improper fractions Mixed number or improper fraction on a number line Fractions on the number line 2 Adding mixed numbers with like denominators Subtracting mixed numbers with like denominators
CCSS.Math.Content.4.NF.B.3d Solve word problems
Figuring out how much pizza is left
involving addition and subtraction of fractions referring to the same whole and having like denominators, e.g., by using visual fraction models and equations to represent the problem.
Using fractions to divide pizzas, pies, and cakes Word problem: What fraction of spider eyes are looking at me?
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Common Core Standard
Khan Academy Videos
Add and subtract fractions with like denominators:
Word problem: What fraction of an hour should the
word problems
piano still be practiced?
Add and subtract fractions with like denominators in recipes
Word problem: How long is this lizard? Adding and subtracting fractions with like denominators word problems
CCSS.Math.Content.4.NF.B.4 Apply and extend previous understandings of multiplication to multiply a fraction by a whole number CCSS.Math.Content.4.NF.B.4a Understand a fraction a/b
Multiplying fractions and whole numbers
as a multiple of 1/b. Conceptual understanding of multiplying fractions
Multiply unit fractions by whole numbers using
and whole numbers
number lines
Multiply unit fractions and whole numbers: sorting
Multiply unit fractions by whole numbers
Whole number and fraction multiplication concept Understanding multiplying fractions and whole
CCSS.Math.Content.4.NF.B.4b Understand a multiple of
numbers
a/b as a multiple of 1/b, and use this understanding to multiply a fraction by a whole number.
Multiply fractions by whole numbers using number lines
Multiply fractions and whole numbers: sorting
Multiply fractions by whole numbers
Multiplying fractions by whole numbers Multiplying fractions word problem: movie marathon Multiplying fractions word problem: milk love Multiplying fractions word problem: pigging out on
CCSS.Math.Content.4.NF.B.4c Solve word problems
pumpkin pie
involving multiplication of a fraction by a whole number, e.g., by using visual fraction models and equations to
Multiplying fractions and whole numbers word
represent the problem.
problems
Multiply unit fractions by whole numbers: word problems
Multiply fractions by whole numbers: word problems
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Common Core Standard
Khan Academy Videos
Multiply fractions and mixed numbers by whole numbers in recipes
CCSS.Math.Content.4 Understand decimal notation for fractions, and compare decimal fractions.
CCSS.Math.Content.4.NF.C.5 Express a fraction with
Converting decimals to fractions example 1
denominator 10 as an equivalent fraction with denominator 100, and use this technique to add two fractions with respective denominators 10 and 100.
Fractions with denominators of 10, 100, and 1000
Add up to 4 fractions with denominators of 10 and 100
Converting decimals to fractions example 2 Converting decimals to fractions example 3 Converting decimals to fractions 1 Decimals on a number line
Add and subtract fractions with denominators of 10, 100, and 1000
CCSS.Math.Content.4.NF.C.6 Use decimal notation for fractions with denominators 10 or 100.
Graph decimals on number lines
Graph fractions as decimals on number lines
Convert fractions and mixed numbers to decimals
Convert decimals to fractions and mixed numbers
Convert decimals between standard and expanded
Decimals on the number line 1 Decimals and fractions on a number line Decimals on the number line 2 Comparing decimals example 1 Comparing decimals example 2 Comparing decimals 1
form using fractions
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Common Core Standard
Khan Academy Videos
CCSS.Math.Content.4.NF.C.7 Compare two decimals to hundredths by reasoning about their size. Recognize that comparisons are valid only when the two decimals refer to the same whole. Record the results of comparisons with the symbols >, =, or <, and justify the conclusions, e.g., by using a visual model.
Compare money amounts
Compare fractions with like numerators or denominators using models
Compare fractions with like numerators or denominators
Compare fractions using models
Compare decimals on number lines
Compare decimal numbers
Put decimal numbers in order
Put tricky decimals in order
Compare decimals and fractions on number lines
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Appendix B The classroom teacher will read each survey question aloud for the students and the students will fill out the survey on paper. Question 1: Are you a o Boy o Girl Question 2: Did you find the videos interesting? o o o o
Very interesting Somewhat interesting Not interesting I don’t know
Question 3: Did watching the videos help you understand the lesson? o o o o
Yes Sometimes No I don’t know
Question 4: Did you watch any of the videos at home? o Yes o No o I don’t know Question 5: What was your favorite part of the videos? (Open answer)
Question 6: What was your least favorite part of the videos? (Open answer)
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