Sapling Learning is an education company (saplinglearning.com) that provides online homework and instruction for the science disciplines. In addition to its learning platform, the company develops interactive labs that support the inquiry process. Each lab comes with suggested homework and clicker questions that probe student understanding of the concepts. This article will offer examples of integrating Sapling Learning's interactive labs with instruction to engage students inside and outside of the classroom. The article will also describe the principles that guide the design of the labs, with particular emphasis on design considerations for touch interfaces (1).
Sapling Learning’s mission is to engage students and empower educators. We aim to empower educators by providing a course management system that automatically monitors student progress. We aim to engage students by providing online homework that gives instant feedback on their understanding of course content. The screenshot below shows how a question appears to students. Our library includes over 10,000 such questions.
The goal of this question is for students to compare different representations of molecules. They can rotate the 3D models, and they have the option to view a hint. Each molecule contains 4 or 5 bonds. The labels include distractors, such as shapes with less than 4 or more than 5 bonds. The question is also randomized so that some students will see SiH4, for example, while others will see SiF4 or SiCl4. This encourages students to collaborate meaningfully on their homework.
One feature of online homework is that students receive immediate feedback on their understanding after they submit an answer. This feature has been associated with improved student performance (2). At Sapling Learning, we have two modes of feedback for incorrect answers: specific and general. For the specific feedback, our authors predict common student errors and provide targeted responses. The image below shows an example of the specific feedback for the question above.
We include general feedback for those errors we cannot anticipate. This ensures that all students get some form of assistance. As shown in the image below, the general feedback for the question above includes a table that contains the formula of each molecule along with 2D and 3D models. This gives students more guidance toward the correct shape. Did students actually label the 2D model of CF4 as square planar? Read on for the results.
Our products span the range from assessment to instruction. We recently launched a series of eBooks for high school science that include videos, 3D animations, and interactive labs. We used HTML5 to develop the content to enable use on multiple platforms. To date, we have created approximately 50 interactive labs for the subjects of physics, chemistry, and biology. Below is an example of one of the chemistry labs.
Click on the image to open a video of the lab.
The goal of this lab is for students to examine the effect of concentration of the pH of a solution. Students can add a common liquid, such as coffee or juice, to the beaker and use the probe to measure the pH. They can add water or open the drain and observe the effect on the color of the liquid. The tick marks along the side of the beaker also enable students to quantify the effect of dilution. In what follows, we describe our design process for the labs (3).
The design of each interactive lab is guided by two types of learning goals: content and process. Our content goals are for students to develop a conceptual understanding of the science topic. Our process goals are to engage students in science by giving them an opportunity to ask their own questions and test their own hypotheses.
For the high school labs, our design goals also align with the Texas Essential Knowledge and Skills (TEKS), the state standards. Below is an excerpt from one of the science concepts (4).
TEKS Chemistry 10F: “The student is expected to investigate factors that influence solubilities and rates of dissolution such as temperature, agitation, and surface area.”
We developed two labs to address this standard: one for solubility, and one for dissolution rate. In both labs, students can dissolve fine or coarse salt or sugar in water, and they can use a hot plate to examine the effects of heating or stirring the solution. In the Solubility lab, students are given measuring spoons to compare the amounts required to reach saturation. In the Rate of Dissolution lab, students are given a timer. We performed the actual experiment ourselves to obtain relative dissolution times.
Our design goals are also informed by research: We consult the chemistry education literature for insight into student ideas. Our set of electrochemistry labs provides an example. In one of the labs, students can build a voltaic cell using half-cells and a salt bridge. We included an option to animate the flow of electrons from the anode to the cathode to confront the student ideas about current flow reported by Sanger and Greenbowe (5).
We apply the idea of implicit scaffolding (6) to create environments that enable students to ask their own questions. This allows us to guide students while giving them a sense of autonomy. A common example of this idea comes from door design: A door that people must push to open should not have a handle that people can pull. Below we use the Specific Heat lab to illustrate our use of affordances and constraints.
The goal of this lab is for students to plan a procedure to determine the specific heat of a metal. Students can drag the cup, the metal block, and the thermometer. Students can also select and identify a mystery metal. They can use the reset button to repeat an experiment.
This lab affords certain actions. The water dropper is poised above the cup to cue students to add water. Likewise, the metal block is poised above the burner to cue students to heat the metal. The balance and the thermometer cue students to measure mass and temperature. Even the dropdown menu cues students to compare the metals.
This lab also constrains certain actions. For example, students can only add water and heat once per experiment. Students are also not able to drag the metal block out of the cup. Part of the reason is to simplify the model, but the main reason is to encourage productive experimentation.
We use two types of user experience testing to ensure that an interface is intuitive: hallway and online. For hallway testing, we literally walk around the Sapling Learning office and ask coworkers to think aloud while using the lab. We occasionally use a screen-capture program to enable us to revisit the tests. After about three users, we begin to observe common interface issues and interpretation errors.
For online testing, we employ a service (UserTesting.com) that provides on-demand usability testing. We create the test and they recruit the testers. Within an hour, we can watch videos of people using the lab and read their responses to our follow-up questions. Here we use the Atom Builder lab to give an example of the feedback.
Click on the image to open a video of the lab.
In this lab, students can build atoms with protons, neutrons, and electrons. They can examine the effect of each particle on the identity of the atom, the charge, and the mass number. The nucleons shake when students build an unstable nucleus. The electrons move so rapidly in the play area that they are hard to locate. Students can click outside the nucleus to remove an electron from the play area. Our representation of the atom was inspired by a Nature article on hollow atoms (7).
For the online user testing, we set up the scenario: “You are a student in an introductory science class. Your teacher has asked the class to use an online lab for homework.” The first task was to explore the lab for a few minutes. The next few tasks were more specific. In the video clip below, one of the testers is using the lab to answer: “What changes the number after the name?”
Click on the image to open a user testing video.
Note how she uses the lab to test her predictions. “Is it the number of electrons? Let’s try it.” The immediate feedback in the lab allows her to develop a rule for the mass number. “I think the number shows how many protons and neutrons are in the atom.” Then she uses the lab to demonstrate the rule. This example suggests that students can learn from the lab without explicit guidance.
We use the results of user testing to make changes to the lab. For example, in the hallway testing for the Atom Builder lab, we saw that some users thought the way to make the nucleus stable was to add the nucleons in the correct order. The image below shows that the locations of the nucleons no longer depend on the order in which they are added to the nucleus.
In the online testing, we saw that some users equated stable and neutral. As shown in the image below, we added the word “nucleus” to the stability readout. We also changed a phrase in the Help text from “build as many stable, neutral atoms as possible” to “stable and neutral atoms”.
In both forms of interface testing, we saw that users were hesitant to click on the Help button. This was particularly the case for male users. The image below shows that the Help button is now an “Info” button, but we are still exploring other ways to make our Help buttons less intimidating.
We also try to address issues in the questions that we write for the lab. Below is a screenshot of one of the questions for the Atom Builder lab. It asks students to classify each atom description as stable and/or neutral to confront the idea that stable and neutral are equivalent.
Note that we encourage students to use the lab to answer the question, as they are not expected to know which combinations of nucleons result in a stable nucleus. The items are also randomized to promote meaningful collaboration. In summary, user testing informs both the design of the lab and the questions that we ask about the lab.
Engage students in lecture
The open design of the interactive labs enables use in a variety of educational settings. Below are two examples of using the Conductivity lab with clicker questions in a lecture environment. The goal of this lab is for students to compare different types of solutions. They can drag the electrodes into a solution to measure the conductivity and view the particles in solution.
One type of clicker question that lends itself well to an interactive lab is a prediction question. For example, an instructor can ask students to predict which light bulb below shows the result when the electrodes are placed in one of the solutions. The instructor can collect student responses and then use the lab to show students the result.
Another type of clicker question is one that generates critical discussion of the interactive lab. For example, water molecules are not shown in the Conductivity lab. An instructor can ask students to select the zoom view below that shows the best representation of water. The first option shows a macroscopic representation, the second shows water molecules floating in water, and the third shows water molecules tightly packed. The instructor can collect student responses and then facilitate a classroom discussion about particulate models of solutions.
Engage students in lab
Our interactive labs are designed to support the inquiry process. For example, the goal of the lab below is for students to investigate precipitation reactions. Students can mix two solutions of ionic compounds and observe whether a precipitate forms. They can also use the results to identify an unknown solution. An instructor can use this lab to ask students to construct the solubility rules rather than to confirm the rules.
Each interactive lab comes with suggested questions. Many of the questions that we write for the labs ask students to collect and analyze data from the lab. An instructor can use this resource to prepare students for the experience of a wet lab. The eBooks for high school also include lab videos. Below is a still from a video about precipitation reactions. An instructor can use this resource to ask students to contrast the physical reaction with its virtual representation.
The interactive labs provide a safe environment for experimentation. Some of our labs contain reactions with safety or waste issues. Others allow procedures that would require equipment that a high school science department may not own. In this way, our interactive labs can enhance and extend the wet lab experience.
Engage students at home
Not surprisingly, an instructor can use our interactive labs with online homework. One strategy is to introduce a concept at home so that students are prepared to apply the concept in class. Many of our questions ask students to notice relationships in the lab. Other questions, like the example for the Atom Builder lab, prompt students to construct a working definition of science terms. Below is a screenshot of a question for the pH lab that asks students to examine how adding water or opening the drain affects the pH of each solution.
We include a link to the interactive lab in the question stem. Since the interactive labs are not randomized, we randomize the questions associated with the labs to encourage students to collaborate. In the example above, the solutions in the table are randomized so that each student is likely to get a different set. We also encourage students to use the lab to answer the question. An instructor can use the same strategy with other online resources and other homework systems.
Engage students anywhere
We develop the interactive labs in HTML5 to enable students to use the labs on any device. This means that we must ensure that our labs work on laptops and tablets, in multiple browsers and platforms. This also means that we must consider touch interfaces in the design of the labs.
The pH lab provides one example of a design consideration. We often use cursor changes to signify when an object is interactive. As shown in the image below, when a student hovers over the button on the water bottle, the mouse cursor changes from a pointer to a hand. We occasionally show a tooltip, such as “add water”, when a student hovers over an interactive object. Both of these cues are not possible on touch interfaces, so we must rely on artistic effects.
The Density lab provides an example of another design consideration. The goal of this lab is for students to design an experiment to determine the density of a spherical object. They can use the balance to measure the mass, and they can use the ruler or water displacement to determine the volume. Students can compare two objects of the same material with different sizes or two objects of different materials with the same size. They can also identify a mystery object.
Click on the image to open a video of the lab on a tablet.
We used a tablet for hallway testing and saw that it was difficult for users to measure the diameter of the small objects because their fingertips covered the objects. In the next iteration, we made the ruler transparent and added the ability to drag the ruler over the objects.
We did a horizontal flip of the interface for another lab after we saw that users’ hands covered the features below their fingers. Touch interfaces are important to consider early in the design process, and user testing on tablets often reveals usability issues.
For teachers: Customization
Sapling Learning pairs each instructor with a “Tech TA”, a subject expert who provides support throughout the semester. One way that our Tech TAs support instructors is by editing our existing content. We also plan to offer customization of the interactive labs. For example, we can add or remove chemicals from a lab to better align with a particular experiment.
Below is a version of the Density lab with objects removed. In this version, the objects are made of the same material. The material is one that has a range of density values. The largest rock does not fit inside the graduated cylinder, and it also maxes out the balance. Students can use the ruler and the average density of the other rocks to determine the mass of the largest rock. Another version of this lab could include rocks with other shapes.
Below is a version of the Density lab with objects added. This version includes an object that floats in water and an object with an irregular shape. Students can use the ruler to determine the volume of the wood ball, and they can use water displacement to determine the volume of the gold nugget.
Another way that our Tech TAs support instructors is by developing new content to address specific learning goals. We plan to provide the same level of support for our interactive labs.
For researchers: Data
Over 200,000 students are using Sapling Learning this semester. This means that many of our homework questions are attempted by thousands of students. Our homework system tracks every incorrect response. We already use this data to gauge difficulty and to ensure that students are getting our specific feedback. Many instructors use this data to shape their lectures.
An education researcher can use this data to uncover common student ideas or to compare student ideas before and after a learning experience. Below is a screenshot of a question that an instructor may assign during a unit on density. The question asks students to use the intensive nature of density to predict the behavior of a small metal block.
More than 1000 students have attempted this question. With the targeted feedback, nearly all students correctly place the metal at the bottom of the beaker. The student paths are even more interesting. The image below shows the five patterns followed by 98% of the students. We see that only 84% of the students were correct on their first attempt. We also see that students were more likely to place the metal in the middle of the beaker than to place it on the surface of the water.
Here we return to the opening question: Did students label the 2D model of CF4 as square planar? Of the roughly 1000 students who attempted this question, only 6% selected this on their first attempt. On the other hand, 19% of students labeled SF4 as tetrahedral on their first attempt. Given the specific feedback that the central atom has one lone pair, most students went on to successfully complete the question.
We are currently working on math labs for a new high school product in addition to developing new interactive labs for science. We are also exploring ways to offer free access to the interactive labs for students and teachers. One plan is to form a community where we can share labs in progress and get feedback on the design. We hope that you are able to apply one of the ideas in this article in your own work, and we look forward to your comments.
(1) This article is based on a presentation given by the author:
Lancaster, K. Engaging students with Sapling interactives. Presented at the 246th ACS National Meeting & Exposition, Indianapolis, IN, September 8-12, 2013; Paper CHED 404.
(2) For an independent case study using Sapling Learning, see:
Parker, L.L.; Loudon, G.M. Case Study Using Online Homework in Undergraduate Organic Chemistry: Results and Student Attitudes. J. Chem. Educ. 2013, 90, 37-44.
(3) For more on challenges unique to the design of interactive chemistry simulations, see:
Lancaster, K.; Moore, E.B.; Parson, R.; Perkins, K.K. Insights from Using PhET’s Design Principles for Interactive Chemistry Simulations. In Pedagogic Roles of Animations and Simulations in Chemistry Courses; Suits, J.P., Sanger, M.J., Eds.; ACS Symposium Series, Vol. 1142; American Chemical Society: Washington, DC, 2013; pp 97-126.
(4) Texas Administrative Code, Title 19, Part II; Chapter 112. Texas Essential Knowledge and Skills for Science; Subchapter C. High School.
(5) Sanger, M.J.; Greenbowe, T.J. Students’ Misconceptions in Electrochemistry: Current Flow in Electrolyte Solutions and the Salt Bridge. J. Chem. Educ. 1997, 74, 819-823.
(6) For more on the application of implicit scaffolding in simulation design, see:
Podolefsky, N.S.; Moore, E.B.; Perkins, K.K. Implicit scaffolding in interactive simulations: Design strategies to support multiple educational goals. Submitted to J. Sci. Educ. Technol.
(7) Van Noorden, R. Bohr’s model: Extreme atoms. Nature 2013, 498, 22-25.
The author would like to acknowledge the content and art teams at Sapling Learning. In particular, she would like to thank Jeff Sims, our interactive developer and animator. The author finds it a funny coincidence that she used to design “sims” for the PhET project and that Jeff lives in Lancaster, PA.