September 2016 – Vol. 29 No. 1

But What Is “Good”?! Learning and Using Observational Skills by Studying Water Taste

Posted: Tuesday, August 5th, 2014

by Joanne Michael

The beginning of the year is a fantastic time to get to know how skilled your students’ observations are when working on an experiment. While there are a number of brain teasers and visual slight-of-hands that can accomplish this, I like to do a lab that I call “Which Water is Water?” to quickly assess their skill set. From doing this, I have an immediate data set of which students are skilled at noticing subtle differences between two or more items, which students can describe something with detail, and which students are good at sitting back and allowing others to do the dirty work. Best of all the students LOVE this lab; they ask me mid-year if they can do it again! I normally do this with my 5th grade classes, but it can be done with any grade level. With the current drought occurring within California, it is also a fantastic time to discuss water sources and conservation.

Collect as many different types of water as you can. I normally get distilled water, tap water (from the drinking fountain at school), filtered water (either bring a Brita®/pur® pitcher from home and filter the school water, or pour some into a bottle from home), and bottled water. For added challenge, select multiple brands of bottled water! Sparkling water can work as well, but as there are obvious bubbles, it makes that one pretty easy to distinguish. Pour each into a large (at least 12 ounce) new clear plastic cup, and write a letter on the outside with a marker to help distinguish the waters from each other. In my science lab, I have the students sit in tables of 4, so each table has a cup with an A, B, C, or D on the outside when they walk in. Each table also has 4 Dixie® cups (or similar), and an empty bowl.

I begin the lesson by reviewing the water cycle, which we discussed in previous years, and where a lot of our water is collected and used around southern California. I also go through the definitions of the various types of water, to make everything as clear as possible. The students then select a type of water, and pour it amongst the four cups. Before tasting, they must smell the water – does it have a scent? They then take a tiny sip, and allow the water to move around their tongue to get as many different “flavors” as possible.

From there, they write observational details about their water. I do not allow them to write “opinion details” – what tastes gross to one person may be absolutely delicious to another, and so that isn’t a scientific observation. Does it taste soapy? Like dirt? Does it have an aftertaste? Taste sweet? Does the flavor absolutely disappear? They write down all observations. I encourage the students to take tiny sips, so that they can do multiple tastings if they need to do so. They can have a group discussion if they would like, but they are to write down their own observations. If the student does not like the taste at all, they can dump the rest of their sample in the bowl; likewise, if they really enjoy it, they can pour more from their big cup. After they have tasted all of the samples, they try to identify which water is which – which sample is the distilled water? The bottled water?

When the class is finished, we take a quick poll as to what they think each sample was, and show the answers. The students are normally surprised at the results – most often, they assume the bottled water is the distilled water, because distilled water is “pure” water – of COURSE it would taste the best! We then discuss the importance of different types of water, keeping our drinking water clean, how to conserve water, etc. Within the span of 45 minutes, I now know which students are skilled at minute observations, which students are leaders within a group, the general skill level at scientific adjectives, and if there are any students that need additional help in fine motor skills. The students are thrilled – they spend an hour drinking water, and not getting in trouble for consuming something in science lab! It sets the stage for the rest of the year for the students as well – they see the expectations in the science lab, and know that we will work hard but have a lot of fun in the process!

Modifications: I do this lab with my 5th grade students, but could very easily be done with any grade level. For added difficulty, only use different brands of bottled water, and try to have the students identify the different brands.

This idea originally came from One Water.


Grade Level: 5th

Science Area: Earth science

Science Standards Reference (1998 version): 5.3.d: Students know that the amount of fresh water located in rivers, lakes, underground sources, and glaciers is limited and that it’s availability can be extended by recycling and decreasing the use of water.

5.3.e: Students know the origin of the water used by their local communities.

Other Subject Area Standards Reinforced: “Going Green”

Title of the Lab: Water is Water

Time Required: Set-up – 10 minutes; Duration- 1 hour

Goal of the Lab (student outcomes): students will use their senses to try to taste the difference between different types of water, and to understand the various processes involved in obtaining the different types of water.

Description/Abstract: Students will taste four different types of water: tap, filtered, sparkling, and distilled. After learning about the process used for each type of water, they will write down which one they think is which, based solely on the taste. Afterwards, the teacher will reveal the answers and lead a discussion as to why they all taste so different.

Materials Needed: (per group of 4)
4 small disposable cups (Dixie® cups work perfectly)
4 larger new cups, labeled A, B, C, D, with the various waters inside
1 small bowl


1) Tell students to pour a little bit of water from cup A into each of the 4 small cups. Do a proper observation of sample A including smell, look, and taste. Write observations on data sheet.  Pour out the rest of water (if they wish) into the bowl in the middle of the table.

2) Repeat for samples B, C, D. The samples may be similar. Have the students do their best to find differences between them all. Offer up suggestions, “Is it fizzy?” “Does it leave an aftertaste?”

3) When all samples have been tested, reveal answers. How many students mixed up the tap water and the bottled water? Why does the distilled water taste so strange? That’s the only one that is actually “pure” water! Show where the various waters came from on a map of California.

Assessment method: Water Worksheet

Joanne Michael is the K-5 science specialist at Meadows Elementary in Manhattan Beach, CA, and CSTA Intermediate Director.

Written by Joanne Michael

Joanne Michael

Joanne Michael is a K-5 Science Specialist for Manhattan Beach Unified, former CSTA Upper Elementary director, and is a current CSTA member.

2 Responses

  1. This is a great lab! I have done a similar lab with distilled vs tap and students are always surprised to find that pure water tastes funny. To be rigorous do a triangle test where two cups are the same and one is different. If tasters can consistently identify the one that is different it means the difference is real.

  2. I second Pete’s opinion about this lab. My version is done when students learn about the needs of living things (in what used to be 7th grade life science)! I really like including one natural mineral water; students are always astounded to learn it isn’t artificially created by a company. I also add an extension where students determine the amount of water they drink in one year and then calculate the supply cost. Another eye opener for them…many think the water coming out of their tap at home is “free.”

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California Science Assessment Update

Posted: Wednesday, October 12th, 2016

by Jessica Sawko

In June 2016 California submitted a waiver application to discontinue using the old CST (based on 1998 standards) and conduct two years of pilot and field tests (in spring 2017 and 2018, respectively) of the new science assessment designed to support our state’s current science standards (California Next Generation Science Standards (CA-NGSS) adopted in 2013). The waiver was requested because no student scores will be provided as a part of the pilot and field tests. The CDE received a response from the U.S. Department of Education (ED) on September 30, 2016, which provides the CDE the opportunity to resubmit a revised waiver request within 60 days. The CDE will be revising the waiver request and resubmitting as ED suggested.

At its October 2016 North/South Assessment meetings CDE confirmed that there will be no administration of the old CST in the spring of 2017. (An archive of the meeting is available at Learn More…

Written by California Science Teachers Association

California Science Teachers Association

CSTA represents science educators statewide—in every science discipline at every grade level, Kindergarten through University.

Some ways to celebrate the 100th anniversary of the National Park Service in your classroom

Posted: Thursday, September 22nd, 2016

by Carol Peterson

1) To celebrate the 100th anniversary of the National Park Service, Google has put together a collection of virtual tours combining 360-degree video, panoramic photos and expert narration. It’s called “The Hidden Worlds of the National Parks” and is accessible right from the browser. You can choose from one of five different locales, including the Kenai Fjords in Alaska and Bryce Canyon in Utah, and get a guided “tour” from a local park ranger. Each one has a few virtual vistas to explore, with documentary-style voiceovers and extra media hidden behind clickable thumbnails. Ideas are included for use in classrooms. Learn More…

Written by California Science Teachers Association

California Science Teachers Association

CSTA represents science educators statewide—in every science discipline at every grade level, Kindergarten through University.

2016 Award Recipients – Join CSTA in Honoring Their Accomplishments

Posted: Thursday, September 22nd, 2016

CSTA is pleased to announce the winners of the 2016 CSTA Awards for Distinguished Contributions, Margaret Nicholson Distinguished Service Award, 2014 and 2015 PAEMST-Science recipients from California, and the 2016 California PAEMST Finalists. The following individuals and organizations will be honored during the 2016 California Science Education Conference  on October 21- 23 in Palm Springs. This year’s group of awardees are truly outstanding. Please join us in congratulating them!

Margaret Nicholson Distinguished Service Award

John Keller

John Keller

The Margaret Nicholson Distinguished Service Award honors an individual who has made a significant contribution to science education in the state and who, through years of leadership and service, has truly made a positive impact on the quality of science teaching. This year’s recipient is John Keller, Ph.D. Dr. Keller is Associate Professor, Cal Poly San Luis Obispo and Co-Director, Center for Engineering, Science, and Mathematics Education, Cal Poly San Luis Obispo. In her letter of recommendation, SDSU science education faculty and former CSTA board member Donna Ross wrote: “He brings people together who share the desire to make a difference in the development and implementation of programs for science teaching. Examples of these projects include the Math and Science Teaching Initiative (MSTI), Noyce Scholars Program, Western Regional Noyce Initiative, and the Science Teacher and Researcher (STAR) program.” Through his work, he has had a dramatic impact on science teacher education, both preservice and in-service, in California, the region, and the country. He developed and implemented the STEM Teacher and Researcher Program which aims to produce excellent K-12 STEM teachers by providing aspiring teachers with opportunities to do authentic research while helping them translate their research experience into classroom practice. SFSU faculty member Larry Horvath said it best in his letter:“John Keller exemplifies the best aspects of a scientist, science educator, and mentor. His contributions to science education in the state of California are varied, significant, and I am sure will continue well into the future.” Learn More…

Written by California Science Teachers Association

California Science Teachers Association

CSTA represents science educators statewide—in every science discipline at every grade level, Kindergarten through University.

NGSS: Making Your Life Easier

Posted: Tuesday, September 20th, 2016

by Peter A’hearn

Wait… What?

NGSS is a big shift. Teachers need to learn new content, figure out how this whole engineering thing relates to science, and develop new unit and lesson plans. How could NGSS possibly make life easier?

The idea that NGSS could make our lives easier came to me during the California State NGSS Rollout #1 Classroom Example lesson on chromatography. I have since done this lesson with high school chemistry students and it made me think back to having my own students do chromatography. I spent lots of time preparing to make sure the experiment went well and achieved the “correct” result. I pre-prepared the solutions and organized and prepped the materials. I re-wrote and re-wrote again the procedure so there was no way a kid could get it wrong. I spent 20 minutes before the lab modeling all of the steps in class, so there was no way to do it wrong. Except that it turns out there were many. Learn More…

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Written by Peter AHearn

Peter AHearn

Peter A’Hearn is the K-12 science specialist in the Palm Springs Unified School District and is Region 4 Director for CSTA.

Celestial Highlights, September 2016

Posted: Tuesday, September 20th, 2016

by Robert C. Victor. Twilight sky maps by Robert D. Miller. Graph of evening planet setting times by Dr. Jeffrey L. Hunt 

Our evening twilight chart for September, depicting the sky about 40 minutes after sunset from SoCal, shows brilliant Venus remaining low, creeping from W to WSW and gaining a little altitude as the month progresses. Its close encounter within 2.5° N of Spica on Sept. 18 is best seen with binoculars to catch the star low in bright twilight. The brightest stars in the evening sky are golden Arcturus descending in the west, and blue-white Vega passing just north of overhead. Look for Altair and Deneb completing the Summer Triangle with Vega. The triangle of Mars-Saturn-Antares expands as Mars seems to hold nearly stationary in SSW as the month progresses, while Saturn and Antares slink off to the SW. Learn More…

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Written by Robert Victor

Robert Victor

Robert C. Victor was Staff Astronomer at Abrams Planetarium, Michigan State University. He is now retired and enjoys providing skywatching opportunities for school children in and around Palm Springs, CA. Robert is a member of CSTA.