Incorporating Authentic Assessments in Chemistry

deflatgate football and pressure valve

Recently, my district made a commitment to helping its teachers reflect and rethink their grading and assessment practices. One of the phrases I kept hearing throughout our staff professional development sessions was authentic assessment. I understood (and agreed with) the basic premise—create more opportunities for students to perform tasks that demonstrate meaningful application of essential knowledge and skills. Doing so involves going beyond, or even potentially replacing, traditional summative assessments at the end of each unit.

While this was (and still is) an intimidating thought for me, I knew any reservations I had stemmed from being asked to step out of my comfort zone—a reason no one should use to justify not doing something that has value. While I have been making some progress this year, with different degrees of success, I am interested in improving my creativity making authentic assessments and hope to gather new ideas from other chemistry educators like yourself.

What is an Authentic Assessment?

The description that helped me understand this phrase best comes from the Center for Innovative Teaching and Learning at Indiana University1:

An authentic assignment is one that requires application of what students have learned to a new situation, and that demands judgment to determine what information and skills are relevant and how they should be used. Authentic assignments often focus on messy, complex real-world situations and their accompanying constraints; they can involve a real-world audience of stakeholders or “clients” as well.


How Do Authentic Assessments Compare to Traditional Assessments?

The table below is based on the work from one of the most well-known advocates for assessment reform, Grant Wiggins.2 When relating this to my own assessments, I realized that even though many of my traditional assessments did not completely fit every description of a typical test, they rarely contained characteristics that would classify it as authentic. Little moments of revelation like this helped me rethink my entire approach toward assessing my students in meaningful ways.


Typical tests

Authentic tasks

Indicators of authenticity

Require correct responses

Require a high-quality product or performance, and a justification of the solutions to problems encountered

Correctness is not the only criterion; students must be able to justify their answers

Must be unknown to the student in advance to be valid

Should be known in advance to students as much as possible

The tasks and standards for judgment should be known or predictable

Are disconnected from real-world contexts and constraints

Are tied to real-world contexts and constraints; require the student to “do” the subject.

The context and constraints of the task are like those encountered by practitioners in the discipline.

Contain items that isolate particular skills or facts

Are integrated challenges in which a range of skills and knowledge must be used in coordination

The task is multifaceted and complex, even if there is a right answer.

Include easily scored items

Involve complex tasks that for which there may be no right answer, and that may not be easily scored

The validity of the assessment is not sacrificed in favor of reliable scoring.

Are “one shot”; students get one chance to show their learning

Are iterative; contain recurring tasks

Students may use particular knowledge or skills in several different ways or contexts.

Provide a score

Provide usable diagnostic information about students’ skills and knowledge

The assessment is designed to improve future performance, and students are important “consumers” of such information.

Table 1 - Comparison of traditonal and authentic assessments.3


When considering the role of authentic assessments in your classroom, I think it is important to realize that authentic assessments complement traditional assessments. Having students demonstrate they can recall information, solve constrained theoretical problems, and provide written explanations are all important aspects of the learning process. But there is a good argument to be made for the limitations in validity of student learning when it is based solely on a traditional assessment that we often disconnect from anything resembling a real-world context.

Though I am simply a mere grasshopper still, I have listed a few examples that describe some attempts I have made at incorporating this mindset into my chemistry classroom. For each of these, I could justify replacing a large portion of that specific unit’s test, maybe even the whole thing.


#1: Stoichiometry—Determine the correct chemical equation for the decomposition of sodium bicarbonate

Though I already wrote a post about this experience, which you can find here, I will give the basic rundown. Students are presented with four different balanced chemical equations that could explain how the atoms are rearranged during this decomposition.



I give them the appropriate materials and they are told to apply their knowledge of stoichiometry and labs skills they have learned to generate enough evidence that supports which of the four chemical equations accurately represents the reaction. Students create their own procedure, decide how to collect/organize their data, and eventually present their argument on a whiteboard using the Claim, Evidence, Reasoning framework.

#2: Ideal Gas Law—Determine the number of moles of gas in this bottle

This idea was given to me by one of my colleagues and I love how deceptively simple it is.

Here is a bottle…figure out how many moles of gas are in the bottle. Students are not directly given any materials. However, they are told that they can use whatever they want, assuming it is safe. The utter lack of spoon-fed directions complemented with little to no guidance from the teacher makes many of them feel like they are facing an impossible challenge. The temporary surprise, frustration, and confusion that follows immediately after they are told their task provides a wonderful insight to their reasoning process and confidence in problem solving.

Though the volume, temperature, and pressure end up being rather simple to determine in order to calculate moles, this challenge forces them in a position where they have to not only know what data they need, but how they are going to get it. Additionally, they need to make certain connections between the data they gathered and how it will help them solve the problem. Some common methods for finding these variables are listed below.

Temperature: Find a thermometer in the room and check the temperature. Make sure to convert to Kelvin.

Volume: Fill up the bottle with water and pour it into a graduated cylinder. This involves concepts like density, measurement, significant figures, and unit conversion.

Pressure: While I do not have a barometer in the room, students eventually resort to looking up the pressure in our city that day on a weather app on their phone. Since the units are typically in inches, they quickly realize some unit conversions need to be made.

Once they make the necessary calculations, they show me their answer and I either give them a pass or tell them to try again.


#3: Gas Laws—Deflategate: Could the under-inflated footballs be the result of environmental conditions of the day?

This idea was inspired by Elizabeth Megonigal and can be read about in greater detail in her J Chem Ed article, Naughty or Nature—Bringing Chemistry to Deflategate3.

Many of my students were already familiar with the well-known controversy that took place between the Patriots and Colts during the 2014-15 NFL season. Students are given a wealth of information from the day of the game as well as experimental results that were eventually determined during the actual investigation. Using their knowledge of gas laws, reasoning and communication skills, they are tasked with creating a compelling argument for defending their answer to the question above which was graded against a known rubric. This was a really cool experience and I plan to write a more detailed reflection of this in the near future.

For more ideas, be sure to check out Lauren Stewart’s post on Practicums in Chemistry

What sort of ideas that reflect an authentic assessment have you tried? I would love to hear from anyone that is willing to share or even potentially collaborate!


1Indiana University - Center for Innovative Teaching and Learning: Authentic Assessment

2Wiggins, Grant. (1998). Ensuring authentic performance. Chapter 2 in Educative Assessment: Designing Assessments to Inform and Improve Student Performance. San Francisco: Jossey-Bass, pp. 21 – 42.

3 Megonigal, Elizabeth. Nature or Naughty: Bringing “Deflategate” to the High School Chemistry Classroom. J. Chem. Educ. 2016, 93, 311—313. (This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.



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Comments 4

Lauren Stewart's picture
Lauren Stewart | Wed, 04/18/2018 - 13:48

I love the simplicity of "determine the number of moles of gas in this bottle." I am making a note to add that to my gas laws unit next year!

Ben Meacham's picture
Ben Meacham | Fri, 04/20/2018 - 16:51

Right??  I thought the same thing when I heard about it.  Heard of someone else using it as a take-home exam.  Thought that was a pretty cool idea too.

Juleen Jenkins-Whall | Tue, 04/24/2018 - 20:51

Early in the year, I give them some samples of a metal and tell them to go find the density.  Its fascinating to watch them struggle with this.  They have to take multiple measurements of mass and volume, find the average and then the percent error.  

 I have modified a lab assesment I saw at an AP summer session of "Make 2.0g of ____."  Students are assigned an insoluble solid (ex/ Calcium carbonate) and they need to determine a way to make and collect it.  They are given a short list of possible reactants that allow double replacement reaction.  They must choose two that can produce their product and then calculate the mass of each reactant needed to make the desired product.  

Nadia Lara | Wed, 04/25/2018 - 14:33

Love this! I really want to do more authentic assessments in my classes. Do your students work in groups? Mine usually do, and I can often tell when one student doesn't quite get what everyone else is doing, but it's hard to substantiate that claim...