Author: sayamindu

Seymour Papert is credited as saying that tools to support learning should have “high ceilings” and “low floors.” The phrase is meant to suggest that tools should allow learners to do complex and intellectually sophisticated things but should also be easy to begin using quickly. Mitchel Resnick extended the metaphor to argue that learning toolkits should also have “wide walls” in that they should appeal to diverse groups of learners and allow for a broad variety of creative outcomes. In a new paper, Benjamin Mako Hill and I attempted to provide the first empirical test of Resnick’s wide walls theory. Using a natural experiment in the Scratch online community, we found causal evidence that “widening walls” can, as Resnick suggested, increase both engagement and learning.

Over the last ten years, the “wide walls” design principle has been widely cited in the design of new systems. For example, Resnick and his collaborators relied heavily on the principle in the design of the Scratch programming language. Scratch allows young learners to produce not only games, but also interactive art, music videos, greetings card, stories, and much more. As part of that team, I was guided by “wide walls” principle when I designed and implemented the Scratch cloud variables system in 2011-2012.

While designing the system, I hoped to “widen walls” by supporting a broader range of ways to use variables and data structures in Scratch. Scratch cloud variables extend the affordances of the normal Scratch variable by adding persistence and shared-ness. A simple example of something possible with cloud variables, but not without them, is a global high-score leaderboard in a game (example code is below). After the system was launched, I saw many young Scratch users using the system to engage with data structures in new and incredibly creative ways.

Although these examples reflected powerful anecdotal evidence, I was also interested in using quantitative data to reflect the causal effect of the system. Understanding the causal effect of a new design in real world settings is a major challenge. To do so, we took advantage of a “natural experiment” and some clever techniques from econometrics to measure how learners’ behavior changed when they were given access to a wider design space.

Understanding the design of our study requires understanding a little bit about how access to the Scratch cloud variable system is granted. Although the system has been accessible to Scratch users since 2013, new Scratch users do not get access immediately. They are granted access only after a certain amount of time and activity on the website (the specific criteria are not public). Our “experiment” involved a sudden change in policy that altered the criteria for who gets access to the cloud variable feature. Through no act of their own, more than 14,000 users were given access to feature, literally overnight. We looked at these Scratch users immediately before and after the policy change to estimate the effect of access to the broader design space that cloud variables afforded.

We found that use of data-related features was, as predicted, increased by both access to and use of cloud variables. We also found that this increase was not only an effect of projects that use cloud variables themselves. In other words, learners with access to cloud variables—and especially those who had used it—were more likely to use “plain-old” data-structures in their projects as well.

The graph below visualizes the results of one of the statistical models in our paper and suggests that we would expect that 33% of projects by a prototypical “average” Scratch user would use data structures if the user in question had never used used cloud variables but that we would expect that 60% of projects by a similar user would if they had used the system.

It is important to note that the estimated effective above is a “local average effect” among people who used the system because they were granted access by the sudden change in policy (this is a subtle but important point that we explain this in some depth in the paper). Although we urge care and skepticism in interpreting our numbers, we believe our results are encouraging evidence in support of the “wide walls” design principle.

Of course, our work is not without important limitations. Critically, we also found that rate of adoption of cloud variables was very low. Although it is hard to pinpoint the exact reason for this from the data we observed, it has been suggested that widening walls may have a potential negative side-effect of making it harder for learners to imagine what the new creative possibilities might be in the absence of targeted support and scaffolding. Also important to remember is that our study measures “wide walls” in a specific way in a specific context and that it is hard to know how well our findings will generalize to other contexts and communities. We discuss these caveats, as well as our methods, models, and theoretical background in detail in our paper which now available for download as an open-access piece from the ACM digital library.

This blog post, and the open access paper that it describes, is a collaborative project with Benjamin Mako Hill. Financial support came from the eScience Institute and the Department of Communication at the University of Washington. Quantitative analyses for this project were completed using the Hyak high performance computing cluster at the University of Washington.

Last week, we presented a new paper that describes how children are thinking through some of the implications of new forms of data collection and analysis. The presentation was given at the ACM CHI conference in Denver last week and the paper is open access and online.

Over the last couple years, we’ve worked on a large project to support children in doing — and not just learning about — data science. We built a system, Scratch Community Blocks, that allows the 18 million users of the Scratch online community to write their own computer programs — in Scratch of course — to analyze data about their own learning and social interactions. An example of one of those programs to find how many of one’s follower in Scratch are not from the United States is shown below.

Last year, we deployed Scratch Community Blocks to 2,500 active Scratch users who, over a period of several months, used the system to create more than 1,600 projects.

As children used the system, Samantha Hautea, a student in UW’s Communication Leadership program, led a group of us in an online ethnography. We visited the projects children were creating and sharing. We followed the forums where users discussed the blocks. We read comment threads left on projects. We combined Samantha’s detailed field notes with the text of comments and forum posts, with ethnographic interviews of several users, and with notes from two in-person workshops. We used a technique called grounded theory to analyze these data.

What we found surprised us. We expected children to reflect on being challenged by — and hopefully overcoming — the technical parts of doing data science. Although we certainly saw this happen, what emerged much more strongly from our analysis was detailed discussion among children about the social implications of data collection and analysis.

In our analysis, we grouped children’s comments into five major themes that represented what we called “critical data literacies.” These literacies reflect things that children felt were important implications of social media data collection and analysis.

First, children reflected on the way that programmatic access to data — even data that was technically public — introduced privacy concerns. One user described the ability to analyze data as, “creepy”, but at the same time, “very cool.” Children expressed concern that programmatic access to data could lead to “stalking“ and suggested that the system should ask for permission.

Second, children recognized that data analysis requires skepticism and interpretation. For example, Scratch Community Blocks introduced a bug where the block that returned data about followers included users with disabled accounts. One user, in an interview described to us how he managed to figure out the inconsistency:

At one point the follower blocks, it said I have slightly more followers than I do. And, that was kind of confusing when I was trying to make the project. […] I pulled up a second [browser] tab and compared the [data from Scratch Community Blocks and the data in my profile].

Third, children discussed the hidden assumptions and decisions that drive the construction of metrics. For example, the number of views received for each project in Scratch is counted using an algorithm that tries to minimize the impact of gaming the system (similar to, for example, Youtube). As children started to build programs with data, they started to uncover and speculate about the decisions behind metrics. For example, they guessed that the view count might only include “unique” views and that view counts may include users who do not have accounts on the website.

Fourth, children building projects with Scratch Community Blocks realized that an algorithm driven by social data may cause certain users to be excluded. For example, a 13-year-old expressed concern that the system could be used to exclude users with few social connections saying:

Fifth, children were concerned about the possibility that measurement might distort the Scratch community’s values. While giving feedback on the new system, a user expressed concern that by making it easier to measure and compare followers, the system could elevate popularity over creativity, collaboration, and respect as a marker of success in Scratch.

I think this was a great idea! I am just a bit worried that people will make these projects and take it the wrong way, saying that followers are the most important thing in on Scratch.

Kids’ conversations around Scratch Community Blocks are good news for educators who are starting to think about how to engage young learners in thinking critically about the implications of data. Although no kid using Scratch Community Blocks discussed each of the five literacies described above, the themes reflect starting points for educators designing ways to engage kids in thinking critically about data.

Our work shows that if children are given opportunities to actively engage and build with social and behavioral data, they might not only learn how to do data analysis, but also reflect on its implications.