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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>LiveHint: Intelligent Digital Support for Analog Learning Experiences</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Joshua D. Fisher</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Stephen E. Fancsali</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Amy Jones Lewis</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Victoria Anne Fisher</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Rob- ert G.M. Hausmann</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Martina Pavelko</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Sandy Bartle Finocchi</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Steven Ritter</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Carnegie Learning, Inc.</institution>
          ,
          <addr-line>Pittsburgh PA 15219</addr-line>
          ,
          <country country="US">USA</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Among the critical expectations that learning stakeholders have for K12 curriculum providers during the current global pandemic are that they provide: (a) support to rectify students' learning loss, (b) resources to help parents support student learning, and (c) greater access to open educational resources. We introduce a mobile-friendly, digital support for analog learning experiences called LiveHint, which currently supports students as they work on assignments in Carnegie Learning's physical worktexts via a chatbot with access to thousands of context-sensitive hints. In addition to expanding the number of courses supported by LiveHint, we discuss possibilities for expanding the scope of activities supported by LiveHint within Carnegie Learning's existing content. We also lay out possibilities for expanding the approach beyond Carnegie Learning's content to teacher-created artifacts (e.g., custom worksheets), hand-offs between instructional modalities, and potential research use-cases for data collected from such a platform.</p>
      </abstract>
      <kwd-group>
        <kwd>Hints</kwd>
        <kwd>Homework</kwd>
        <kwd>Textbooks</kwd>
        <kwd>Dialogue-Based Tutoring</kwd>
        <kwd>Intelligent Tutoring Systems</kwd>
        <kwd>Parent Support</kwd>
        <kwd>Caregiver Support</kwd>
        <kwd>K-12 Pandemic Response</kwd>
        <kwd>K-12 COVID-19 Response</kwd>
        <kwd>Mathematics Education</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>1.1</p>
    </sec>
    <sec id="sec-2">
      <title>Introduction</title>
      <sec id="sec-2-1">
        <title>Equity &amp; Support for Learning in a Global Pandemic</title>
        <p>
          During the flu pandemic of 1918, schools in the United States closed for as many as
fifteen weeks [
          <xref ref-type="bibr" rid="ref1 ref2">1, 2</xref>
          ]. During that time, some teachers likely sent home assignments, and
students could practice with learning materials of the time (e.g., practicing math by
writing with chalk or charcoal on a slate), but, by and large, time devoted to chores or
to paid work (prior to changes in child-labor laws made in subsequent decades) was
perceived as more valuable for both students and their families [
          <xref ref-type="bibr" rid="ref3">3</xref>
          ]. Despite substantial
increases in the technology used for learning and the extent to which K-12 education is
prioritized in the 21st century, many solutions deployed by schools, both under normal
operations and to respond to the COVID-19 pandemic, are necessarily analog (e.g.,
paper worksheets, textbook work, and work in consumable worktexts like Carnegie
Learning's MATHbook), owing especially to disparities in access to certain technologies
(e.g., laptop computers and broadband internet access).
        </p>
        <p>
          Whether digital or analog, solutions provided by curriculum providers and
educational technology developers face serious challenges as learning transitions from
largely synchronous K-12 classrooms environments to more asynchronous, remote
learning contexts. Nascent research efforts are only beginning to understand this
transition (e.g., [
          <xref ref-type="bibr" rid="ref4 ref5">4, 5</xref>
          ]). Among the most important expectations for curriculum providers,
according to a recent survey of 900 teachers and administrators conducted by EdWeek
Market Brief [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ], are "support to make up for students' learning loss," "resources to help
parents support student learning," "creating more opportunities for equitable learning,"
and "greater access to open educational resources." Any technology that claims to meet
these expectations must be platformed in a way that is sensitive to persistent disparities
in the availability of online access and digital technology between lower- and
higherincome households. Only around 54% of lower-income Americans had access to a
desktop or laptop computer in the home in 2019, while 71% had access to smartphones.
The percentage of these Americans who rely on their smartphone to access the Internet
has more than doubled over the past six years [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ]. Given the more widespread adoption
of mobile technologies (e.g., smartphones with some form of access to the internet),
Carnegie Learning seeks to develop more equitable technological solutions to support
learning during such analog experiences, not only to meet the immediate need created
by the novel coronavirus but to also enhance learning (and our understanding of remote
learning) more generally.
        </p>
        <p>
          Capitalizing on relatively broad access to smartphones with access to the Internet, in
what follows, we describe a dialogue-driven, mobile application called LiveHint.
Carnegie Learning deployed LiveHint as a rapid response solution to support student work
(as well as caregivers supporting those students) with its MATHbook worktexts, which
are an integral part of its widely-deployed blended curriculum solutions that include the
MATHia intelligent tutoring system (formerly Cognitive Tutor) [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ]. In addition to
describing the current deployment of LiveHint, we describe important avenues for future
research and development, including ways that LiveHint points toward a new
conception of textbooks that combines the familiarity and convenience of traditional analog
text with the flexibility and support provided by intelligent tutoring systems.
1.2
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>Carnegie Learning’s MATHbook &amp; Worktexts</title>
        <p>Carnegie Learning's print worktexts and e-textbooks (collectively referred to as
MATHbook) are designed to promote active learning and are structured to allow
students to collaboratively engage with others, think critically, and gain a deeper
understanding of math at the middle school and high school levels. Teacher support materials
for these write-in consumable worktexts or e-books include topic introductions, pacing
support tools, suggestions for grouping students, and recommendations for how to
connect group and individual learning. Digital slide decks are available for each lesson for
teachers to use in class or in remote-learning settings. In addition, a Skills Practice
companion to the basal worktext provides targeted practice of skills and mathematical
concepts for each topic.</p>
        <p>In Carnegie Learning’s recommended, blended implementation, collaborative
student work guided by instructors and MATHbook is coupled with individual work in
MATHia adaptive software in a 60%-40% time split (60% collaborative work and 40%
individual work in MATHia). The current global pandemic has upended the extent to
which this blended implementation can be realized in face-to-face settings, but various
technologies (e.g., remote conferencing and video chat software, among others)
provides means by which key facets of these blended implementations can be maintained,
and, hopefully, flourish.
1.3</p>
      </sec>
      <sec id="sec-2-3">
        <title>Intelligent Digital Support for Traditional Learning Resources</title>
        <p>To help address remote-learning needs in response to the global pandemic, Carnegie
Learning introduced direct-instruction videos for each worktext lesson, openly
available to support students and parents at home, along with other resources collected in an
@Home Learning Library. In addition, a “live coach on-call” human tutor has been
made openly available to students and parents via email or text. Teacher support
delivered by Carnegie Learning’s professional learning and development experts now
includes virtual 1:1 coaching and troubleshooting. In addition to these resources,
Carnegie Learning seeks to provide more support for students (and their caregivers or parents
supporting them), especially those students and their families experiencing poverty, as
they use physical worktexts, but possibly in the absence of a laptop computer or
broadband Internet access. To further enhance the experience of learners using print
worktexts, we designed a digital companion to textbook homework assignments,
LiveHint.
2</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>LiveHint</title>
      <p>
        Lessons in Carnegie Learning’s MATHbook generally start by tapping into students'
prior knowledge and using worked examples and step-by-step instruction to support
students as they build concepts. Next, tasks transition to challenging students to reason
about the implications of what they just learned and to make connections to go further.
When students work on homework assignments associated with lessons, they need to
consolidate what they've learned and embed it within practice, which is provided as a
section of MATHbook homework assignments. While working in this practice section,
students need support as they are strengthening and maintaining already existing, but
brittle and weakly constructed, problem-solving schemata [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
      </p>
      <p>
        LiveHint supports students as they work on assignments by, first, reiterating the
directions and then providing three to five hints on each practice problem in the
homework assignment via a chatbot. Students can access these hints on a smartphone,
desktop or laptop computer, tablet, or, in the future, potentially through smart speaker
devices. A desktop/laptop demo is also available [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. The initial release of LiveHint covers
five of Carnegie Learning’s standard middle/high school courses, from Grade 6 to
Grade 8, Algebra I, and Integrated Math I (hints for the latter deployed several weeks
after the Grades 6-8 and Algebra I) and includes nearly 3,900 hints for close to 1,000
homework practice questions. In the 2021-2022 school year, students will be able to
access LiveHint via QR codes printed in their worktexts; such QR code functionality
also opens up opportunities to digitally support crowd-sourced (especially
teacher-created) content.
      </p>
      <p>
        Hint authoring for LiveHint is informed by research [
        <xref ref-type="bibr" rid="ref10 ref11">10, 11</xref>
        ] suggesting that effective
hints:
•
•
•
•
are concrete,
model the process of determining the sought-after solution,
suggest courses of action rather than just state general principles, and
are specifically related to the problem at hand.
      </p>
      <p>
        When they are free to do so, students often do not ask for assistance (e.g., after making
an error [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ]), and students often do not realize what kind of help they should seek (e.g.,
hints vs. answers [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]). In their conversation with the LiveHint chatbot, students do not
enter a natural-language query, but simply reference the question they are working on,
and hints developed for that question are provided. Students are then given the
opportunity to rate each hint, according to how useful they found it. Math experts,
practitioners, instructional designers, and researchers can respond to usage and rating data, along
with written feedback, to improve the quality of the hints provided. We return to discuss
the potential for this continuous improvement process later.
      </p>
      <p>
        Providing hints in assignments may help induce both teachers and students, who
might not otherwise have done so, to provide or engage in post-lesson retrieval
opportunities, regardless of ability. Vaughn and Kornell [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ], for example, found that
students provided with hints were more likely to engage in retrieval versus restudy. In
contrast, students who were not provided hints chose to restudy. Thus, providing hints
may induce students to use a more effective (but more difficult) study technique [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ].
2.1
      </p>
      <sec id="sec-3-1">
        <title>A LiveHint Example</title>
        <p>An example of a LiveHint sequence of directions and a hint (Fig. 1) is taken from the
current Carnegie Learning MATHbook for Grade 8 (Course 3), in a homework
assignment for a lesson on classifying numbers as rational, irrational, integers, natural
numbers, terminating or repeating decimals, and so on.</p>
        <p>The problem scenario is as follows:
“Ling groups the following numbers together with the rationale that
they are all repeating decimals: 12/18, –16/3, 3 1/3. Do you agree
with Ling's grouping? Explain your reasoning.”</p>
        <p>MATHbook provides the following directions to the student, which are re-iterated by
LiveHint, as illustrated in Fig 1:
“Read the scenario. Ling groups the numbers 12/18, –16/3, and 3 1/3
together with the rationale that they are all repeating decimals. Do
you agree with Ling’s grouping? Explain your reasoning.”</p>
        <p>The first hint provided by LiveHint, after a student selects, “See a hint.” (also
illustrated in Fig. 1):
“To determine whether a fraction is a repeating decimal, divide the
numerator by the denominator. Think about the fraction –16/3. The
negative sign doesn't matter to whether or not it can be written as a
repeating decimal.”</p>
        <sec id="sec-3-1-1">
          <title>The second hint provided by LiveHint is: “Think about the mixed number 3 1/3. The whole number doesn't matter to whether or not it can be written as a repeating decimal. If 1/3 is a repeating decimal, then 3 1/3 is a repeating decimal.”</title>
        </sec>
        <sec id="sec-3-1-2">
          <title>The third, and final, hint provided by LiveHint is: “The fraction 12/18 in lowest terms is 2/3. Is that a repeating decimal?”</title>
          <p>2.2</p>
        </sec>
      </sec>
      <sec id="sec-3-2">
        <title>Student Feedback</title>
        <p>After each hint is provided, LiveHint’s chatbot asks the student, “How helpful was that
hint?” (Fig. 2) The student’s response is captured on a 5-point Likert scale with emoji
facial expressions ranging from an angry face (a rating of 1, “not at all helpful”) to a
wide-mouthed grin with hearts for eyes (a rating of 5, “exceedingly helpful”). While
not a direct measure of learning, we take learner satisfaction as a preliminary proxy for
hint effectiveness. In the future, we plan to explore questions of whether (and the extent
to which) learner satisfaction ratings for hints correspond to the effectiveness of these
hints in improving problem solving and other learning outcomes.
We deployed LiveHint and publicized its availability to a small set of pilot school
districts in May and June of 2020. Despite the substantial disruption of the COVID-19
pandemic and how late in the school year this piloting took place, we consider data
from 173 LiveHint sessions in which learners1 received at least one hint, having
identified a particular problem in MATHbook, viewed the directions, and selecting to receive
a hint. The median session time across sessions with at least one hint was 1 minute, 17
seconds, suggesting that the design intent of keeping learner interactions with LiveHint
relatively brief is being met overall. During these 173 sessions, learners provided a
rating for 124 hints they were provided (approximately 72% of provided hints),
suggesting that students do not provide ratings for hints they receive with some frequency.</p>
        <p>
          Following research that considers learner response times in the context of
help-seeking and hint use (e.g., [
          <xref ref-type="bibr" rid="ref16 ref17">16, 17</xref>
          ]) and as an illustration of analyses we expect to conduct
with LiveHint data (and the types of research we hope to catalyze by sharing LiveHint
data), Fig. 3 provides a plot of mean hint rating provided by students over these 124
rated hints (across Grades 6-8, Algebra I, and Integrated Math I2) versus the amount of
time learners spent (presumably) working with hints, before requesting another hint,
seeking help on another problem, or logging off. While certainly not definitive, a
preliminary pattern indicates that learners tend to be more satisfied with the hints with
1 Logging functionality to identify unique users was implemented part-way through piloting and
suggests that most users launched LiveHint once or twice. This logging functionality suggests
that greater than 104 unique users are represented among these 173 LiveHint sessions with at
least one hint that we consider.
2 Integrated Math I content deployed late in the pilot and consequently has only two rated hints
in these preliminary data.
which they spend less time (with hints rated ³ 3 tending to have average times less than
a minute), indicating that hints on which they spend more time could be less helpful
and targets for revision. We look forward to collecting more data during the summer
and during the fall as we support learners, instructors, parents, and caregivers adjusting
to new learning contexts as a result of the COVID-19 pandemic.
        </p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Future Work</title>
      <sec id="sec-4-1">
        <title>Extending Content Reach &amp; More Sophisticated Tutoring</title>
        <p>In addition to expanding the number of published courses supported by LiveHint, we
are exploring expanding the reach of LiveHint within courses, moving beyond support
for practice activities in the worktexts to include other independent activities as well as
those that are often completed independently or by students together with parents or
caregivers, either remotely or at school.</p>
        <p>
          Future plans may also include widening the scope of student and other stakeholder
needs that LiveHint supports, including providing hints in Spanish and other languages
and increasing the use of video hints and hints accompanied by either static or dynamic
images. In addition to providing hints and querying students as to the perceived value
of such hints, intermediary problem step or partial solutions to MATHbook problems
could also be accepted as LiveHint input to better understand learner problem solving
(e.g., understanding strategies adopted by students in solving particular problems) and
hint effectiveness by providing more direct measures of learning (e.g., correctness of
solutions). Although current versions of LiveHint do not accept student-generated
input, we are actively exploring the application of dialog-based tutoring in this context
[
          <xref ref-type="bibr" rid="ref18">18</xref>
          ].
        </p>
        <p>
          LiveHint affords the opportunity to develop new supplemental products that can be
connected to and "tutored" through LiveHint, including test preparation materials,
intervention resources (e.g., for Response to Intervention and/or Tiers 2 and 3 in
multitiered systems of support or MTSS [
          <xref ref-type="bibr" rid="ref19 ref20">19, 20</xref>
          ]), games (e.g., scavenger hunts), and other
extension materials. Authoring tools could be built that would allow teachers to create
LiveHint support for their own custom-made worksheets or other analog learning
resources. Open repositories of such custom materials could be tagged with data about
standards, competencies, and/or fine-grained knowledge components or skills [
          <xref ref-type="bibr" rid="ref21">21</xref>
          ] to
which particular elements of such materials correspond. The availability of this kind of
content, coupled with such meta-data, in an open repository would make assignments
of appropriate content easier, and far less time-consuming, for instructors. Further,
mappings of such content to knowledge components or other forms of competencies
could enable linking LiveHint to other instructional technologies, including intelligent
tutoring systems like MATHia, for example, by updating a student’s estimates of skill
mastery (i.e., MATHia’s skillometer [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ]) based on their work in the analog MATHbook
materials and interactions with LiveHint. Such potential linkages of analog and digital
learning experiences represent important avenues for the future of the textbook.
3.2
        </p>
      </sec>
      <sec id="sec-4-2">
        <title>Improved Artificial Intelligence &amp; Instructional Hand-Offs</title>
        <p>
          Previous work has considered using data to predict and potentially inform “instructional
hand-offs” [
          <xref ref-type="bibr" rid="ref22">22</xref>
          ] or transitions between instructional applications or between the use of
an instructional application and engaging with a human resource (e.g., an online, human
tutor, a video chat with a teacher, or, in less pandemic-addled times, a face-to-face
interaction with a teacher or peer). In the context of LiveHint, instructional hand-offs
could happen in at least three ways: (1) connecting a struggling student with a human
teacher or tutor (e.g., allowing a student to launch a video chat with a teacher or tutor
from within LiveHint), (2) connecting a struggling student with a peer to engage in
collaborative learning, or (3) connecting a struggling student with an appropriate
instructional technology or application (e.g., suggesting that a student work in a particular
topical workspace in Carnegie Learning’s MATHia based on patterns of responses to
hints and/or other questions or problem-steps in LiveHint). Any of these hand-offs
require technical integration work (e.g., integrating live video chat functionality into
LiveHint) as well as the development of statistical models to predict:
• when such hand-offs are most likely to benefit the student most,
• if a particular peer, online tutor, or instructor (assuming access to instructors
that are not the student’s classroom teacher) is a good match, and
• ensuring that hand-offs make efficient use of scarce, valuable time available
to instructors, tutors, and/or a student’s peers.
        </p>
      </sec>
      <sec id="sec-4-3">
        <title>Prospects for Research, Learning Engineering, &amp; Data Sharing</title>
        <p>
          LiveHint represents a new facet of support for students’ analog interactions with
analog/physical learning artifacts (i.e., Carnegie Learning’s consumable MATHbook) and
also serves as an evidence-gathering tool for continuous improvement and learning
engineering efforts, pointing to particular content in MATHbook that may require review
and revision. For example, particular practice questions that are the subject of LiveHint
sessions with greater frequency than others may be highlighted as requiring revisions
to better facilitate student practice. In addition, student feedback is likely to provide
insight into better hint construction and authoring, and experimental A/B tests can be
conducted to determine if particular alternative strategies for providing and/or
authoring hints are likely to yield better learning. Further, data from the platform will be made
available via mechanisms like the Learner Data Institute
(http://www.learnerdatainstitute.org) and LearnSphere (http://www.learnsphere.org) to provide resources to the
educational data science research community for exploring the so-called “assistance
dilemma” (i.e., the tension between providing and withholding assistance like hints in
ways that are conducive to learning) [
          <xref ref-type="bibr" rid="ref23">23</xref>
          ], modeling hint response time [
          <xref ref-type="bibr" rid="ref16 ref17">16, 17</xref>
          ], the
effectiveness of hint authoring schemata and of particular hints, dialogue-based
tutoring, and other pressing questions for how to deliver effective, adaptive instruction
across both analog and digital learning modalities. We are excited to explore
opportunities to better understand and improve real-world, classroom-based, and remote
learning with datasets collected from authentic, multi-modal learning contexts.
4
        </p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Acknowledgments</title>
      <p>This work is generously supported by Schmidt Futures and the National Science
Foundation via The Learner Data Institute (Award #1934745). Opinions expressed herein
are those of the authors and do not necessarily reflect those of Schmidt Futures or the
National Science Foundation.</p>
    </sec>
  </body>
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