My good friend and colleague, Natalie Gerum over at the Centre for Student Involvement and Careers, is one of the most creative and careful educators I know. When it became clear that we would be teaching online this term, my single first thought was – “How do we build meaningful community in an online forum?”

Natalie is an expert community builder, and we both recognize the (well documented) importance of strong and early relationship building to the academic success of first year students. (For more on this, I suggest a book called “Challenging and Supporting the First Year Student” by Betsy Barefoot, M. Lee Upcraft, and John N. Gardner). (Full disclosure: I’m not actually teaching first year students this year, but I’ve taught first year for decades, and I think first year principles are so ingrained in my teaching that they are there to stay.) So I called Natalie.

In relationship building for education, one of the critically important but often overlooked pieces is what Natalie calls “the in between times”. These are those unscripted times when students walk into a classroom and sit down next to someone. They look around. They roll their eyes when the professor is late. They chat with the person sitting next to them. I whined, “How am I going to do this in Zoom?” And Natalie said… “well, you start your Zoom class. Let the students join, and disappear. Maybe show up 5 minutes late.” 

(See? She’s a genius.)

And so I began my term by opening up my Zoom lectures 15 minutes early and I post a PowerPoint slide of something to do. Sometimes it’s colouring (via Zoom annotation), or origami instructions, or a crossword puzzle. I share my computer music and play my extensive collection of 70s songs (so they really have something to talk about). And then I walk away and make coffee. When I come back 20 minutes later, community has happened. They’ve shared recipes on the chat forum. They’ve started a discussion group (without me). They’ve made friends.

Which just goes to support my tried and true teaching truth: sometimes the most important things we can do as educators is get out of their way. (More on this later…)

This term, our Biol 342 lab is working at home. This course is designed for Combined Majors in Science students and this is their lab on cake. In this lab, they compare volume of a standard cake recipe with chemical leavening to volume of a cake where they have stoichiometrically balanced the acid and base involved in the leavening to a third cake were they have substituted the type of acid.

Preparation and Supplies

1 oven or toaster oven
1 9” cake pan OR 1 8” square pan
all purpose flour (1 1/2 c)
sugar (1 c)
baking cocoa (1/4 c) (NOTE: this is different than hot chocolate. Cocoa is unsweetened)
salt (1/2 t) (NOTE: “t” = teaspoon)
baking soda (1t)
vanilla extract (1t)
cider or white vinegar (1T) (NOTE: ’T’ = tablespoon)
another food safe acid (such as orange juice or lemon juice)
vegetable oil (1/3 c)
cold water (1 c)
a ruler or measuring tape


Students work in groups of 3 (remotely). One person bakes an old King Arthur Flour cake recipe. A second will bake the same cake, but with a molar balanced amount of vinegar rather than the amount prescribed in the recipe. The third person will bake the same cake, but will swap out the vinegar with another acid.

The basic cake: This recipe is very old. It was developed during world war II when rationing was common and eggs (a leavening agent) were scarce. This cake is so popular, it was selected as the Recipe of the Centuries by King Arthur Flour. The original recipe can be found here, which includes a simple icing if you’d like to include that on your cake: https://www.kingarthurflour.com/recipes/king-arthurs-original-cake-pan-cake-recipe

Instead of eggs, this cake recipe uses baking soda and vinegar to leaven the cake. Leavening is the addition of air pockets into your baked product. If you think of breaking open a loaf of bread, there are often large air pockets inside. These pockets form from CO2 released during leavening. The gas is trapped in the matrix of the flour, forming pockets. This process can be accomplished biologically through yeast, which metabolize sugar and release CO2, egg whites, which hold air pockets when whipped, or other agents. Leavening can also be accomplished chemically with the addition of an acid and a base.

We assume that our different recipes will result in cake with the same volumes. In your lab notebook, write a testable scientific hypothesis.

The basic recipe (person 1 bakes this)

Ingredients
1 1/2 cups (177g) All-Purpose Flour
1 cup (198g) sugar
1/4 cup (21g) cocoa powder
1/2 teaspoon salt
1 teaspoon baking soda
1 teaspoon vanilla extract
1 tablespoon (14g) vinegar, cider or white
1/3 cup (67g) vegetable oil
1 cup (227g) cold water

Instructions
(1) Preheat your oven to 350°F (see lab 1 for adjustments your oven may need). Lightly grease an 8″ square or 9″ round pan that’s at least 2″ deep. You can use a very small amount of oil or butter to grease the pan.
(2) Whisk the dry ingredients together in a medium-sized bowl. Whisk the vanilla, vinegar, vegetable oil, and water in a separate bowl. Pour the wet ingredients into the bowl of dry ingredients, stirring until thoroughly combined. Pour the batter into the prepared pan.
(3) Bake the cake for 25-30 minutes, until a toothpick or knife inserted into the centre comes out clean, or with a few moist crumbs clinging to it. Carefully remove from the oven using oven mitts and let cool.
(4) Using a tape measure and your geometry skills, calculate the volume of your cake. The entire class should discuss how to do this to make sure all our data is obtained the same way.
(5) Upload a photo of your cake with the volume and your assigned type of cake (1, 2 or 3)

Work with your lab group to answer the following questions. Make sure these are in your lab notebook.

1. Evaluate the basic recipe above. Ignoring the cocoa, what is the acid present in this recipe? What is the base?

The recipe calls for 1 teaspoon of baking soda. The chemical formula is NaHCO3.

2. What is the molecular weight of baking soda?

3. One teaspoon of baking soda weighs approximately 4.8 g. How many moles are in 1 teaspoon of baking soda?

Vinegar is acetic acid. The chemical formula is CH3COOH.

4. What is the molecular weight of acetic acid?

When baking soda and acetic acid combine, the following reaction occurs:

NaHCO3 + HC2H3O2 → NaC2H3O2 + H2O + CO2

5. What is the gas given off during this reaction? (This will leaven your cake)

6. Balance the equation above. (Reminder: Count number of each element on each side and make sure nothing is gained or lost during this process…)

7. How many moles of acetic acid will you need to completely react with all the baking soda called for in the recipe?

8. What is the weight of acetic acid required?

9. One teaspoon of vinegar weighs approximately 4.8 g. What volume of vinegar will you add to your perfectly balanced cake?

A perfectly balanced cake (Person 2 bakes this)
Ingredients
1 1/2 cups (177g) All-Purpose Flour
1 cup (198g) sugar
1/4 cup (21g) cocoa powder
1/2 teaspoon salt
1 teaspoon baking soda
1 teaspoon vanilla extract
the amount of vinegar calculated above
1/3 cup (67g) vegetable oil
1 cup (227g) cold water

Instructions
(1) Preheat your oven to 350°F (see lab 1 for adjustments your oven may need). Lightly grease an 8″ square or 9″ round pan that’s at least 2″ deep. You can use a very small amount of oil or butter to grease the pan.
(2) Whisk the dry ingredients together in a medium-sized bowl. Whisk the vanilla, vinegar, vegetable oil, and water in a separate bowl. Pour the wet ingredients into the bowl of dry ingredients, stirring until thoroughly combined. Pour the batter into the prepared pan.
(3) Bake the cake for 25-30 minutes, until a toothpick or knife inserted into the centre comes out clean, or with a few moist crumbs clinging to it. Carefully remove from the oven using oven mitts and let cool.
(4) Using a tape measure and your geometry skills, calculate the volume of your cake. The entire class should discuss how to do this to make sure all our data is obtained the same way.
(5) Upload a photo of your cake with the volume and your assigned type of cake (1, 2 or 3)

For the third recipe, you will substitute the acid in the cake.
Choose an edible acid from your kitchen. Orange or lemon juice is a good choice. Work with your group to answer the following in your lab notebook:

1. What is the acid ingredient you chose?
2. What is the balanced reaction of your acid with baking soda? (NOTE: you can look this up)
3. What percentage of your ingredient is actually acid? (i.e. orange juice is about 1.5% acid)
4. How much of your ingredient do you need to add to include enough acid to react with all the baking soda?

The remainder of the volume of your ingredient is mostly water, so adjust the water in the recipe as necessary. (If you use orange juice, you may not need to add any water…)

A new acid cake (Person 3 bakes this)
Ingredients
1 1/2 cups (177g) All-Purpose Flour
1 cup (198g) sugar
1/4 cup (21g) cocoa powder
1/2 teaspoon salt
1 teaspoon baking soda
1 teaspoon vanilla extract
the amount of your acid ingredient calculated above
1/3 cup (67g) vegetable oil
1 cup (227g) cold water – adjusted for water in your acid

Instructions
(1) Preheat your oven to 350°F (see lab 1 for adjustments your oven may need). Lightly grease an 8″ square or 9″ round pan that’s at least 2″ deep. You can use a very small amount of oil or butter to grease the pan.
(2) Whisk the dry ingredients together in a medium-sized bowl. Whisk the vanilla, acid, vegetable oil, and water in a separate bowl. Pour the wet ingredients into the bowl of dry ingredients, stirring until thoroughly combined. Pour the batter into the prepared pan.
(3) Bake the cake for 25-30 minutes, until a toothpick or knife inserted into the centre comes out clean, or with a few moist crumbs clinging to it. Carefully remove from the oven using oven mitts and let cool.
(4) Using a tape measure and your geometry skills, calculate the volume of your cake. The entire class should discuss how to do this to make sure all our data is obtained the same way.
(5) Upload a photo of your cake with the volume and your assigned type of cake (1, 2 or 3)

Before enjoying your cake, let’s think back to that hypothesis you generated. How will you test this hypothesis?

To start, you will make some simple measurements and calculate the volume of your baked cake. (Your cake is likely domed in the centre, so one good way might be to measure the height of your cake at the edge, and use this to calculate the volume of your cake base. Then measure the height of your cake at the centre and calculate the volume of the domed “lid”. You will be making assumptions on the shape of this dome, but this should be a close estimate.)

Enter your volume calculations into your lab notebook. Also enter the volume of your cake into with the type of cake you baked (1,2, or 3).

By the end of the week, we will have collectively baked a lot of cakes. How will we evaluate cake volume quantitatively to test our hypothesis?
Because we have 3 populations (basic, balanced, and new acid), we will use an ANOVA test. (Note for future: If we had 2 populations, we could use a t-test).

How do I build community in my Zoom classrooms? How do I honour the trauma my students have experienced this year, collectively and individually? How do I burn-to-the-ground the lab class I had carefully and recently built in the before-times, in order to create something better for an at home experience?

These are the questions I have struggled with, and these are the questions I cannot yet fully answer. When asked if I would take on teaching a laboratory course during a pandemic, I immediately agreed, simply because I know our students need lab courses. At the time, the fall term was unknown. (We knew we would be partially online, possibly partially face-to-face.) Like most of us, my primary goal when designing this course was to create a highly flexible experience that could be accessible to students under various stages of quarantine, in different areas of the world, in different time zones, and with the understanding that any of us could become sick or be required to care for sick household members at any time.

My fundamental goal academically is to create a safe place for students to explore science, practice scientific principles, and build confidence in their abilities as budding scientists. To do this work in a home-lab environment requires building community in my classrooms. I have enough experience working with young adults to know that this sometimes happens best when I purposefully get out of the way. I start each class early and arrive “late” to give students the gift of unscripted in-between moments they would normally have while sitting in a lecture hall, waiting for class to start. I offer unscripted activities (colouring pages or origami) and play music while students are waiting (and I’m making coffee). The term is just starting, but this simple act has given them ownership of that time and space. They have shared recipes, built chat rooms, and formed study groups on their own. I count these as steps towards what I hope will become an active thriving learning space over the next few weeks. 

Within the space of the first week, we have also addressed the trauma experienced by all of us. I invited students to share stories by annotating over a map of the world. We honoured the disappointment for a lab experience that they will not get. (As one example, there was a student who was really hoping to gain experience with PCR and gel electrophoresis.) This week we will explore this further by asking questions about a pencil. When we ask different members of the academy what questions they have about a pencil, we get widely different questions. Personally, I want to know what wood the pencil is made of. I can answer this in the lab – the techniques to do this are familiar to me – which is possibly why I ask that specific question. But to be honest, that’s pretty boring. If I take the pencil and walk down Main Mall to Physics, we have physicists who are world experts in graphite – and have recently used graphene as a superconductor. They would ask amazing brilliant questions that I wouldn’t think of. My colleagues in history may ask about the development of the current pencil since it’s invention in Napoleon Bonaparte’s army. A poet may ask what words are trapped inside that pencil, waiting to get out. The point of this exercise is to recognize that asking profoundly diverse questions is what makes membership in this academy important. The exact techniques each of us know are minor things. I can show a student how to do PCR in one afternoon. (And I will invite them to come by the lab next year, if they choose, and I will do just that.) The part that is exciting is asking the questions. And in our case, asking the questions specifically so that they can be soundly addressed with scientific methods. To further address the specific nature of this term,  I offer extra flexibility with due dates, as needed. I have delivered supplies to students quarantining because of a delayed return to Canada. My promise to myself and to my students is to be accessible and to help problem solve as dynamic needs arise. 

The excitement of a new possibility in education is not lost by the frantic nature of this exact moment. I know we can build classes and courses that can be better – or only possible – in an at-home learning environment. This principle has driven me forward. What can we do at home that we could not do in a face-to-face lab? In what ways can this experience be not merely adequate, but better, in a home learning environment? There are certainly massive things we have lost this year as educators and learners, but it’s possible that we have the opportunity to engineer equal amounts of gain.