False lizards? Pseudosaurs!

There is nothing fifth graders love as much as making stuff up!  When I saw Skot Caldwell’s post back in February called “Dinosaur Discoveries“, I knew it was an activity my students would love!  Imagine creating your own dinosaur and giving it a name that had clues to its characteristics — much like the actual dinosaurs! When we look at some familiar dinosaur names, we see:


The stegosaurus lived about 150 million years ago.  It was a herbivore with small teeth, which no doubt made it necessary to eat constantly.  As you can see in the picture, the stegosaurus had bony plates along its spine.  If we look at its name, we see that it has two bases:  <stege> from Greek stegos “a roof” and <saur> from Greek sauros “lizard”.  When the first stegosaurus fossils were found in Colorado, they were named by Othniel C. Marsh (1877).  It was thought at first that the bony plates functioned as a type of covering or roof for the dinosaur.  Many scientists since have wondered about the function of those plates.  Have you noticed that there is a connecting vowel <o> in this name?  It is the vowel that is typically used to connect bases that are Greek in origin.  Have you also noticed that the suffix on the Greek word for “roof” is <os> and there is a <us> suffix on this word instead?  Saurus is the Latinized form of the Greek sauros.


The velociraptor lived about 75 million years ago.  It was a carnivore with sharp teeth, especially towards the back.  This dinosaur was unique because it was a biped.  It could move much faster than larger quadruped dinosaurs.  If we look at its name, we see that it has two bases:  <veloc> from Latin velocis “speedy, swift” and Latin raptor “robber”.  Have you noticed that there is a connecting vowel <i> in this name?  It is one of the vowels (<e>, <i>, <u>) that is typically used to connect bases that are Latin in origin.  The velociraptor was named in 1924 by Henry Fairfield Osborn.  He felt that the name reflected such a swiftly moving carnivore.


The brachiosaurus lived about 100 to 150 million years ago.  It was an herbivore that fed on foliage that was higher up than what other dinosaurs could reach.  This dinosaur was huge!  It was about 85 feet long and weighed between 30 and 45 metric tons!  If we look at its name, we see that it is also a compound word with two bases:  <brachi> from Greek brakhion “an arm” and <saur> from Greek sauros “lizard”.  Since both bases are of Greek origin, we are not surprised to see them connected with an <o> connecting vowel.  As in stegosaurus, we see the Latinized <us> suffix.  The brachiosaurus was named by Elmer Riggs in 1903 when he found fossils in western Colorado.  He named it to point out that the front legs are considerably longer than the back legs.

As we can see, dinosaurs were named to reflect their characteristics.  I shared Skot Caldwell’s post with my students.  They loved the drawings and information each “paleontologist” in Skot’s class included on their posters.  They were hungry to create their own.  Once they had named their pseudosaur (false lizards), I asked them to write about them.  I wanted to know their size and weight.  I wanted to know how they moved and ate. I wanted to know if they lived with others of their kind or if they were loners.  I wanted to know how their characteristics (indicated in their names) were used in their daily lives.  This was a writing that took little nudging.  This was fun writing!

Building Cars Powered by Hot Air

Sir Isaac Newton.  That’s where this project began. Sir Isaac Newton and his three Laws of Motion.

Law Number One:  An object at rest tends to stay at rest.  An object in motion tends to stay in motion.  These conditions cannot change without being acted on by a force.

Law Number Two:  Force equals mass times acceleration.  The more force, the more acceleration.

Law Number Three:  For every action there is an equal and opposite reaction.

We talked about these laws and were helped with our understanding of them by watching this Youtube video:

The students, in groups of two, were about to build cars.  The body and wheels were cut from a styrofoam meat tray.  The axle, to which the wheels were held steady with clay, was a wooden stir stick.  The axle was positioned in a straw which was taped to the bottom of the car body.  The car was powered by a balloon.  All of the materials came as part of a kit that I purchased from Carolina Biological .  What I liked about having this as a kit is that everyone had the exact same materials and the exact same set of directions.  Each pair of students had to read and follow around 30 directions in order to complete their car.

The engagement and cooperation within the groups was impressive.  I had them read through the directions with their partner before coming to get the materials.  I wanted them to have an idea of where this was going, and what the materials were for.  Once they had the materials, they read aloud the directions carefully and began assembling their car.

On the second day of class, students were fine tuning.  Once the car was ready for testing, the students went into the hall outside our room to make sure the wheels were steady and the car moved straight.  There were quite a few cars that veered to one side or another.  In that case the students took the car back in to make adjustments to the wheels.  When the cars were “competition ready”, we went down to the cafeteria to race them.  Here is video of that for each of my three classes.

Two of the cars from the third class went extraordinary distances.  The winner went 331 inches (27 1/2 feet)!  The second highest distance was 318 inches (26 1/2 feet).  No other car all day went even half that distance!  At this point there was so much to talk about!

Why did some of the cars not move at all?
Why did the wheels keep falling off?
How were the winning cars different from the others?

The first thing we did back in the classroom was interview the builders of the two winning cars.  The four students involved gave a lot of credit to the wheels of their cars.  They spent time making sure they were uniformly round.  They sanded them to help the car roll smoothly.  And they measured to make sure the axle was as close to the center of the wheel as possible.  Then they used the clay to make them snug on the axle.  No wobbling!

Next we were ready to review Newton’s Laws of Motion.

We considered the second law: Force equals Mass times Acceleration.  The balloon was the force that powered the car.  Could we alter that? Would it help?  Would more balloons result in more force?  Will several balloons of different sizes lose all their air at the same rate?   What would happen if the mass was increased?  How would that impact the speed or distance?  What if it was decreased?  What could we make the body and wheels from besides styrofoam?

We considered the first law:  An object in motion tends to stay in motion and an object at rest tends to stay at rest unless acted upon by a force.  What force caused the cars to slow down and stop?  Was it just the lack of air in the balloon?  What about friction?  What would happen if we altered the wheels?  What else could we make them out of?  What if we varied their width?  How important is it to cut them so they are perfectly round?  How important is it to measure to find the exact center of the wheel when attaching it to the axle?

We considered the third law:  For every action there is an equal and opposite reaction.  The air from the balloon is being released in one direction, but the car is moving in the opposite direction.  Does the position of the balloon matter?  Does the angle of the balloon and straw matter?  Does the order of the different sized balloons matter?

Equipped with the experience of having already built one car along with the understanding gained from discussing the Laws of Motion, the same groups were asked to build another car.  This time they could use whatever they wanted.  The only thing I discouraged was bringing manufactured wheels off of a toy car.  I put out cardboard, more balloons of different sizes, cardboard tubes and the remaining supplies that came with the initial kit.  The students got started, knowing that they would have the opportunity to bring additional supplies from home.

On day four of this activity, the students had some time to get their cars “competition ready”.  We had a car show (it seemed necessary now that no two cars looked alike).  It was so interesting to see the variations.  During work time, those who sought to use five balloons realized that it was difficult to keep the air in three while trying to blow up the others.  In the end, three balloons was the most that anyone used.  Here are the cars and then races from the three classes:

Even when the cars didn’t leave the starting line, the students laughed and enjoyed this challenge!  In the end, the group whose first car went the furthest, built a second car that also went the furthest!  Their second car was quite different from their first car in that the wheels in the second car were Kerr jar lids!  They struggled during work time in keeping them from wobbling, but by the time the race was run, they had figured that out!

Another group used plastic bottle caps with holes drilled for the axle.  The wheels worked beautifully, but this group struggled with attaching their balloon.  Two other interesting sets of wheels were made out of cardboard tubes.  One group used rubber bands around the tubes to grip the floor!  These two groups struggled with attaching the wheels securely to an axle.

At the beginning of class the next day, I asked the students to share what they had learned while doing this project:

  1.  The cardboard wheels went faster than the styrofoam wheels.
  2.  The wheels on each axle needed to be the same size.
  3.  The wheels needed to be sanded smooth.
  4.  It really helped having a partner to talk with and to help hold parts while taping.
  5.  Having more balloons didn’t always work.  It was difficult to inflate and release several balloons all at once.  Sometimes the first balloon was leaking air as the second was being filled.
  6.  It gets too crowded to have too many balloons.
  7.  The car body needs to be big enough to keep the balloons off the floor.
  8.  Large balloons worked better than small ones.
  9.  Masking tape worked well to tape the wheels to the axle.

When you watch the races of both car 1 and car 2, it is pretty obvious that overall there was more success with car 1.  But in the end that didn’t matter.  It wasn’t the end product that was the most important thing here.  It was the mission and the process.  It was the student input, the focus and the cooperation.  Everyone had moments of frustration, but they worked through those moments.  Students cheered each other on and made this a memorable fun activity.  When asked if I should repeat this activity next year, ALL students said, “YES!”

From Graduation to Tardigrades

It’s always difficult to be absent.  I spend a lot of time thinking about the right activity to leave for the students.  This week, I thought about the fact that my fifth graders will soon graduate from our elementary school and move on to the middle school.  I thought that it might be interesting to have them look closer at the word <graduation> and the family it is part of.  I decided to have them start by reading over a list of related words that I provided.  At the top of the page were the words ‘Latin gradus‘.  Beneath that I wrote the denotation of the Latin noun gradus – “a step; a step climbed; a step toward something; something rising by stages”Then they read the definitions for each word out loud and talked as a whole class about how each word related back to the denotation given.  Here is the list of words they were given.

graduation  – When you have reached the top step in something, and there is a celebration.

grade – a degree of measurement.

gradually – something happening in stages.

gradual – something happening in stages.

grading – assign a number to.

graded – having assigned a number to something.

grader – person who assigns a number to something.

upgrade – upward slope – something a step better.

graduate – one who holds a degree or reached a step in education.

downgrade – a downward slope – something a step worse.

centigrade – divided into 100 degrees, as a scale.

degrade – a step worse in condition – to break down or deteriorate.

gradient – an inclined part of a road – a slope.

tardigrade – slow stepper – a water-dwelling, eight-legged,  micro-animal.

plantigrade – the way humans walk  on their soles with heels touching the ground.

retrograde – directed or moving (stepping) backward.

After having read and discussed each word, they were to think about what the modern English base might be for this group of words.  After they established that, they were to write a word sum for each word and then to fill in a blank matrix that was provided.

The day I returned, I looked over the matrices they had turned in.  I was surprised to see that a few students thought that <grad> was the base, and that <e> was a suffix.  Considering that, I began to wonder what other misunderstandings were out there.  I decided to repeat the part of the activity in which the matrix was filled in, so I could talk about the choices made and hear the students vocalize the reasons for those choices.  I made a video of what I did with one of my three classes.  It went similarly in all three classes.

As we went through this activity, I was reassured that many of the students have a great understanding of the structure of words.  I wish you could have seen the anxious hand fluttering in the front row when Ana recognized that of <up>, <down>, <de>, and <retro>, only <de> was a prefix!  The other three had in common the fact that they were bases and would be part of a compound word when joined with <grade>!

As usual, this dive into structured word inquiry led us to a few more fascinating orthographical finds!  We talked a bit about the word retrograde, and how retro, which is now used as an adjective, is actually of clip of retrograde.  I asked if they knew the word retrospect.  I used it in a the following sentence:  “In retrospect, I shouldn’t have used so much fertilizer on my radishes!”  Since we had recently experimented with growing radishes, students understood that I meant “looking back”.  We also talked about what kinds of things were considered retro – things like clothing, music, hairstyles, dances, and more.

Next we looked at an extreme close up of a tardigrade.

(This undated image released by Bob Goldstein and Vicki Madden taken with an electron microscope, shows a micro-animal “tardigrade” also known as a water bear, at the UNC in Chapel Hill, N.C. In Jan. 2015. Read more: http://www.dailymail.co.uk/sciencetech/article-3015185/Alien-life-midst-incredible-creatures-Antarctica-revealed.html#ixzz4h0jHmVxv )

What a fascinating creature this “slow stepper” is!  It can withstand extreme temperatures at both ends of the spectrum as well as extreme pressures and radiation!  After we looked at a few Googled images, the students begged to know more.  I found this video:

Watching a tardigrade rehydrate was especially interesting.  It is thought that when they curl up and lose all but a bit of their water, they can exist for quite a while.  The word ‘cryptobiosis’ was used to describe this state.  We had to pause and think about that word.  We knew from previous word studies that <bi> was Greek for “life”,  and we had recently come across <crypt> as we were doing a special pseudosaur project based on what we saw happening in Skot Caldwell’s classroom.  The Greek base <crypt> has to do with hiding, and according to Etymonline, <osis> is “a word forming element expressing state or condition.”  If you put all that together, we can understand the word ‘cryptobiosis’ to be the “state of hiding life”.

After watching this video, we wondered if we would find tardigrades in our own woods behind our school.  My husband, who used to work at a water treatment plant, said they are commonly found in the water.  As a matter of fact, about ten years ago he shot a video through his microscope lens and suspects that there were tardigrades present.  I can’t wait to look again at the video and share it with my students.   We just never know where a word investigation will take us.   This ended up being such a fun discovery kind of day!