Growing students’ understanding of ratio, proportions, measurement and slope
Grow Beasts – plunk ‘em in water and four or five days later they’ve grown! (Take 'em out and they shrink back down.) Students measure, estimate, predict growth rates, measure some more, compile data, plot points, crunch numbers, and generally get excited, using math to make sense in an active, inquiry environment.
October 2017
Kathryn and Kristi Pihl are two fabulous primary grades teachers and I am lucky enough to have worked with them for some time now on the use of Grow Beasts in their classrooms. We are giving a talk this Friday at the Northwest Math Conference in Portland, Oregon. Stop by and see us if you are lucky enough to be at this excellent conference. Come and get a Grow Beast of your very own! "Grow Beasts: Growing understanding of measurement and inquiry in the primary grades"
12:30-1:30 PM on Friday, 10/13/2017 Here, courtesy of the Pihls, is a sample plan for the use of Grow Beasts in a primary grades classroom:
September 2017
As part of a science unit focused on measurement, all of the third graders grew their own Grow Beasts at Tiffany Park Elementary in Renton, Washington.
The students measured their beasts daily, using centimeters as their standard unit, and as a class they kept track of three additional Grow Beasts grown in Teriyaki sauce, Canola oil and Tapito sauce. To conclude the unit, they held a discussion about why the Grow Beasts grow differently in different liquids. They wondered whether salt might affect growth. Good thinking third graders! How could you test that?
July 2017 We always grow a class Grow Beast of one kind or another in the "Active Learning" class at Seattle University during the summer session. Check out this summer's Grow Beast (Grow-a-Boyfriend!)
and the class Grow Beast stories for 2017 here: http://teed5280.wikispaces.com/GrowBeasts
Click to go to the page with data file and graph
April 2016
Ms. Pihl and her second grade internship class are working with a crop of Grow Beasts at Meridian Park Elementary in Shoreline, Washington. They have just finished growing them and measuring them with paperclips. Now they will come out of the water and the students will track them as they shrink back to more or less their original size.
Shrink, Grow Beasts, shrink!
June/July 2015
This summer it's a Grow Dino in our Active Learning class here at Seattle University. It splashed in (grown in ambient temperature water) at 3PM on 23 June and was removed from the water in the evening of 1 July. It has been drying out and returning to its former more or less svelte and diminutive stature (see chart below). We measured both length and height.
I am on sabbatical and doing some work at Western Sydney University'sSchool of Education. A student teacher in the teacher certification program at UWS tried Grow Beasts with his Year 5 class and they were a big hit!
We started our Grow Seal at 2:30PM on Tuesday afternoon, June 24. Its length, measured from nose to tail, was 9.5 cm. The seal spent its formative time in a gallon-size zip-lock bag of water, traveling often though not extensively. It was removed from the water and allowed to dry out on a very warm and sunny day, after 162 hours in the wet. The weather in the drying out phase went back and forth between sunny and cloudy with cooler nights and occasional rain. Grow Seal was left behind and got no measurements :-( over the long 4th of July weekend. By the 8th of July it had returned to its original length of 9.5 cm. We concluded the data gathering at 9:30AM on 10 July.
March 2014
Ms. Behrend teaches 6th grade at Seattle Girls' School.
She has just completed a very nice unit with Grow Beasts!
June 25, 2013 -
We are growing a Grow-Tiger in my "Active Learning" course at Seattle University.
Here is a link to the spreadsheet with the data:
The Grow-Tiger was immersed at ~3:30PM on June 25, 2013.
We have, at right, a chart depicting the tiger's length as a function of time. The tiger was removed from water on July 3rd at 192 elapsed hours (8 days). At that point its growth had more or less stopped. The weather during its drying out phase has been more or less sunny here in the Pacific NW so the tiger's decline in length has been steady.
May 6 - 13, 2013
We have grown another herd of Grow Beasts. The 6th graders at Seattle Girls School worked in small groups to grow some in water. Then everyone got one of their own and selected their own liquid.
July 16, 2012
We grew a new crop of Grow Beasts in my Active Learning class for Master in Teaching candidates at Seattle University. Each student grew a couple of beasts and created some excellent stories to accompany the descriptions of the experiments and the data. Click here to have a look.
June 25, 2012
We grew a Grow-Penguin in my Active Learning class at Seattle University.
If you are interested, come on over , scroll down to 2012 and take a look at the data.
(You can see the penguin in the last slide of the Zombie sequence below :-)
I will be talking about Grow Beasts and their use in math classrooms at the NCTM (National Council of Teachers of Mathematics) 2012 Annual Conference in Philadelphia, on April 26, 2012. Here are my presentation slides:
July 11, 2011
We are growing a dinosaur! It started at 11.4 cm and was placed in room temperature water at 3:30PM on Wednesday, June 22nd.
Here is a spreadsheet showing its growth over nearly three weeks:
The students in Ms. True's and Ms. Winger's classroom (grades 1-3) at Kimball Elementary in Seattle, Washington have grown a crop of Grow Beasts. They tried water, chocolate milk, pop, orange juice, and coffee!
I went to visit them last week and could see that they got some good growth and learned a lot about measurement. I am now growing a Grow Beast in warm water, hoping to get some super-sized growth. I have named it KimballRex. Click here for more details on the growth of KimballRex.
March 15, 2011
A Grow Beast grown in Red Wine Vinegar and one grown in tap water, for comparison:
====Thanks, Claire!
==
November 30, 2010
We are growing a class Grow Beast here in Seattle. It is growing in room temperature water. This is part of our math methods (K-8) class. The data are available here.
Thanks to those who attended the Grow Beast session at the 49th NW Math Conference in Spokane. I have added your names to my list and will let you know when we are going to grow a new crop of GBs - sometime in late November. In the meantime, keep the notes coming about how you are using GBs in your classrooms ( mroddy@seattleu.edu ).
September 21, 2010
Now that the new school year is underway, please send me news, brief or involved, about what you have done or plan to do with Grow Beasts in your classrooms. I will be at the 49th NorthWest Math Conference in early October and would love to be able to tell folks at that gathering about some new ways in which GBs are being used to teach math, science and beyond.
We have been growing another crop of GrowBeasts. Also, one "Ginormous Grow Frog." You can catch up with all of our beasts on my Active Learning class wiki site:
When you get there be sure to check in on a few of the students' Grow Beast pages. They did some great work! - Many stories and a few videos about the lives of the GBs.
April 30, 2010
Hello to all of you who attended the NCTM session in San Diego!Thanks for making that such an interesting and enjoyable hour (50 minutes?). I hope that you have grown your grow beast, recorded some measurements and given some thought to how you might use them to help your students get involved in learning some math in your classroom.
March 8, 2010
We are growing a herd of Grow Beasts!
Here in Seattle we now have about 20 Grow Beasts out there growing in different conditions. Most of them were started on Monday, the 8th. They will be in their respective liquids (some in tea, some in orange juice, some in soapy water, etc.) for about 72 hours. At the end of the week I will post growth data for the herd. March 12, 2010
They have grown! (or not...)
We ended up growing 15 Grow Beasts in various conditions. we discovered from this that GBs do not grow very well in some liquids and at some temperatures. Loads of good data!
Shown below is a chart showing the data that are contained in this spreadsheet:
Here (at left) is a graph depicting the growth of three Grow Beasts. All three were grown in room temperature water for about 128 hours and then removed and allowed to dry, and shrink. The advertising on the packages of two of the Grow Beasts claimed, in part: "Grows 400%." (What that means is not entirely clear.) I paid about $0.22 for each of these two. The advertising on the package of the third claimed, in part: "Grows 6 times its original size!" I paid about $0.42 for this one.
Questions: Which of the three Grow Beasts depicted at left are which? (Red, Blue, or Yellow)? Did any of them live up to the claims made in their advertising? Did I get my money's worth? :-) (The answer to that last one is YES! They are great fun to grow!)
for the spreadsheet containing the measurements made on all three GBs over the course of about two and a half weeks.
Resources:
Here is the PowerPoint presented at the NCTM (National Council of Teachers of Mathematics) 2010 Annual Conference in San Diego, on April 24, 2010.
Here is a sample middle or high school-level Grow Beast project involving lots of experimentation, shared data and math! "Where can I get my own Grow Beasts?"
If, however, you are in Australia (where I was July 2014 - January 2015) the shipping from Oriental Trading is expensive.
Here is an alternative source for alternative (bigger) Grow Beasts: http://www.dinosaurcorporation.com/dinosaurs10.html
Here: is a brief introduction that will guide you through the processes of joining and editing a wiki space. It's easy.
The Grow Beast Wiki Site
Growing students’ understanding of ratio, proportions, measurement and slope
Grow Beasts – plunk ‘em in water and four or five days later they’ve grown! (Take 'em out and they shrink back down.) Students measure, estimate, predict growth rates, measure some more, compile data, plot points, crunch numbers, and generally get excited, using math to make sense in an active, inquiry environment.
October 2017
Kathryn and Kristi Pihl are two fabulous primary grades teachers and I am lucky enough to have worked with them for some time now on the use of Grow Beasts in their classrooms. We are giving a talk this Friday at the Northwest Math Conference in Portland, Oregon. Stop by and see us if you are lucky enough to be at this excellent conference. Come and get a Grow Beast of your very own!
"Grow Beasts: Growing understanding of measurement and inquiry in the primary grades"
12:30-1:30 PM on Friday, 10/13/2017
Here, courtesy of the Pihls, is a sample plan for the use of Grow Beasts in a primary grades classroom:
And here are guide sheets to accompany the plan:
Krisit Pihl: pihlk584@edmonds.wednet.edu
Mark Roddy: mroddy@seattleu.edu
As part of a science unit focused on measurement, all of the third graders grew their own Grow Beasts at Tiffany Park Elementary in Renton, Washington.
The students measured their beasts daily, using centimeters as their standard unit, and as a class they kept track of three additional Grow Beasts grown in Teriyaki sauce, Canola oil and Tapito sauce. To conclude the unit, they held a discussion about why the Grow Beasts grow differently in different liquids. They wondered whether salt might affect growth. Good thinking third graders! How could you test that?
July 2017
and the class Grow Beast stories for 2017 here:
http://teed5280.wikispaces.com/GrowBeasts
April 2016
Ms. Pihl and her second grade internship class are working with a crop of Grow Beasts at Meridian Park Elementary in Shoreline, Washington. They have just finished growing them and measuring them with paperclips. Now they will come out of the water and the students will track them as they shrink back to more or less their original size.
Shrink, Grow Beasts, shrink!
June/July 2015
This summer it's a Grow Dino in our Active Learning class here at Seattle University. It splashed in (grown in ambient temperature water) at 3PM on 23 June and was removed from the water in the evening of 1 July. It has been drying out and returning to its former more or less svelte and diminutive stature (see chart below). We measured both length and height.
Here's the spreadsheet:October 2014
Grow Beasts Down Under
I am on sabbatical and doing some work at Western Sydney University's School of Education. A student teacher in the teacher certification program at UWS tried Grow Beasts with his Year 5 class and they were a big hit!His lesson plan is here:
Note that the "Outcomes" reference the Mathematics Standards for New South Wales, Australia.
June 2014
Our Active Learning class at Seattle University has a Grow Seal in progress.Here is a the spreadsheet for 2014's Grow Seal:
We started our Grow Seal at 2:30PM on Tuesday afternoon, June 24. Its length, measured from nose to tail, was 9.5 cm. The seal spent its formative time in a gallon-size zip-lock bag of water, traveling often though not extensively. It was removed from the water and allowed to dry out on a very warm and sunny day, after 162 hours in the wet. The weather in the drying out phase went back and forth between sunny and cloudy with cooler nights and occasional rain. Grow Seal was left behind and got no measurements :-( over the long 4th of July weekend. By the 8th of July it had returned to its original length of 9.5 cm. We concluded the data gathering at 9:30AM on 10 July.
March 2014
Ms. Behrend teaches 6th grade at Seattle Girls' School.She has just completed a very nice unit with Grow Beasts!
June 25, 2013 -
We are growing a Grow-Tiger in my "Active Learning" course at Seattle University.Here is a link to the spreadsheet with the data:
The Grow-Tiger was immersed at ~3:30PM on June 25, 2013.
We have, at right, a chart depicting the tiger's length as a function of time. The tiger was removed from water on July 3rd at 192 elapsed hours (8 days). At that point its growth had more or less stopped. The weather during its drying out phase has been more or less sunny here in the Pacific NW so the tiger's decline in length has been steady.
May 6 - 13, 2013
We have grown another herd of Grow Beasts. The 6th graders at Seattle Girls School worked in small groups to grow some in water. Then everyone got one of their own and selected their own liquid.July 16, 2012
We grew a new crop of Grow Beasts in my Active Learning class for Master in Teaching candidates at Seattle University. Each student grew a couple of beasts and created some excellent stories to accompany the descriptions of the experiments and the data. Click here to have a look.June 25, 2012
We grew a Grow-Penguin in my Active Learning class at Seattle University.If you are interested, come on over , scroll down to 2012 and take a look at the data.
(You can see the penguin in the last slide of the Zombie sequence below :-)
June 27, 2012
I was given a Zombie Grow Beast - a first for me!Here is a brief slide show:
media type=custom key=19671878
April, 2012
I will be talking about Grow Beasts and their use in math classrooms at the NCTM (National Council of Teachers of Mathematics) 2012 Annual Conference in Philadelphia, on April 26, 2012. Here are my presentation slides:July 11, 2011
We are growing a dinosaur! It started at 11.4 cm and was placed in room temperature water at 3:30PM on Wednesday, June 22nd.
Here is a spreadsheet showing its growth over nearly three weeks:
March 28, 2011
The students in Ms. True's and Ms. Winger's classroom (grades 1-3) at Kimball Elementary in Seattle, Washington have grown a crop of Grow Beasts. They tried water, chocolate milk, pop, orange juice, and coffee!I went to visit them last week and could see that they got some good growth and learned a lot about measurement. I am now growing a Grow Beast in warm water, hoping to get some super-sized growth. I have named it KimballRex. Click here for more details on the growth of KimballRex.
March 15, 2011
A Grow Beast grown in Red Wine Vinegar and one grown in tap water, for comparison:====Thanks, Claire!
==
November 30, 2010
We are growing a class Grow Beast here in Seattle. It is growing in room temperature water. This is part of our math methods (K-8) class. The data are available here.October 9, 2010
Thanks to those who attended the Grow Beast session at the 49th NW Math Conference in Spokane. I have added your names to my list and will let you know when we are going to grow a new crop of GBs - sometime in late November. In the meantime, keep the notes coming about how you are using GBs in your classrooms ( mroddy@seattleu.edu ).September 21, 2010
Now that the new school year is underway, please send me news, brief or involved, about what you have done or plan to do with Grow Beasts in your classrooms. I will be at the 49th NorthWest Math Conference in early October and would love to be able to tell folks at that gathering about some new ways in which GBs are being used to teach math, science and beyond.
Mark Roddy ( mroddy@seattleu.edu )Seattle University
July 9, 2010
We have been growing another crop of GrowBeasts. Also, one "Ginormous Grow Frog." You can catch up with all of our beasts on my Active Learning class wiki site:
http://teed5280.wikispaces.com/GrowBeastsWhen you get there be sure to check in on a few of the students' Grow Beast pages. They did some great work! - Many stories and a few videos about the lives of the GBs.
April 30, 2010
Hello to all of you who attended the NCTM session in San Diego! Thanks for making that such an interesting and enjoyable hour (50 minutes?). I hope that you have grown your grow beast, recorded some measurements and given some thought to how you might use them to help your students get involved in learning some math in your classroom.
March 8, 2010
We are growing a herd of Grow Beasts!
Here in Seattle we now have about 20 Grow Beasts out there growing in different conditions. Most of them were started on Monday, the 8th. They will be in their respective liquids (some in tea, some in orange juice, some in soapy water, etc.) for about 72 hours. At the end of the week I will post growth data for the herd.March 12, 2010
They have grown! (or not...)
We ended up growing 15 Grow Beasts in various conditions. we discovered from this that GBs do not grow very well in some liquids and at some temperatures. Loads of good data!Shown below is a chart showing the data that are contained in this spreadsheet:
In this chart the Grow Beasts' lengths (y-axis) are plotted against the hours elapsed (x-axis).
Contact me at
mroddy@seattleu.edu
(206)296-5765
Here (at left) is a graph depicting the growth of three Grow Beasts. All three were grown in room temperature water for about 128 hours and then removed and allowed to dry, and shrink. The advertising on the packages of two of the Grow Beasts claimed, in part: "Grows 400%." (What that means is not entirely clear.) I paid about $0.22 for each of these two. The advertising on the package of the third claimed, in part: "Grows 6 times its original size!" I paid about $0.42 for this one.
Questions: Which of the three Grow Beasts depicted at left are which? (Red, Blue, or Yellow)? Did any of them live up to the claims made in their advertising? Did I get my money's worth? :-) (The answer to that last one is YES! They are great fun to grow!)
Click
Resources:
Here is the PowerPoint presented at the NCTM (National Council of Teachers of Mathematics) 2010 Annual Conference in San Diego, on April 24, 2010.
Here is a brief paper about the use of Grow Beasts in the classroom:
Here is a sample middle or high school-level Grow Beast project involving lots of experimentation, shared data and math!
"Where can I get my own Grow Beasts?"
There are many places to buy Grow Beasts. Here's one: http://www.orientaltrading.com/ (Search for the term, "Growing Dinosaurs."
http://www.orientaltrading.com/api/search?Ntt=growing+dinosaur ) It's not expensive. You can order a package of four dozen for only $8.99.
Here's another: LooseInTheLab. Go here for their store:
http://www.looseinthelabscience.com/cat-supplies/chemical/dinosaur-gro-beasts.html
If, however, you are in Australia (where I was July 2014 - January 2015) the shipping from Oriental Trading is expensive.
Here is an alternative source for alternative (bigger) Grow Beasts:
http://www.dinosaurcorporation.com/dinosaurs10.html
Here: is a brief introduction that will guide you through the processes of joining and editing a wiki space. It's easy.
Dr. Mark Roddy
Seattle University - College of Education
Master in Teaching Program