Pine Cones :: Fall Nature Study

With the end of summer and the public school kids absent from our neighborhood, we begin our nature walks in a more relaxed, low-key environment. I know from past experience that I will have fewer families join us for our excursions … regardless of when I schedule the outing. This is perfectly fine with me.  A smaller group is certainly more intimate and we now look forward to longer excursions and all-day outings farther from home.

Last week, we chose to walk down to our neighborhood park for nature study on pine cones.  We met two other families there … one new to homeschooling.  Upon arrival, we selected a dry cone and placed it in a tub of water.  The kids shared what they expected to happen … a couple expected the cone get bigger like a sponge as it absorbed water.  It was a delight to show them that the water made the cones close up to protect the seeds.  We talked about nature’s design and I encouraged them to try the simple experiment again at home with other types of cones.

The 4 kiddos pictured here have been nature journaling for quite some time.  They are getting very adept at their illustrations and my little guy has just begun to narrate to me more information he’d like to include (okay … I admit, I had to encourage him and asked him questions to elicit what he knew) … but it is a start.  DD, on the other hand, has begun to sketch what is of interest to her on her own.  While the girls were collecting cones, they had also observed a few small birds flitting about the pines.  MeiLi recognized it right away … it’s a Nuthatch … see how it walks upside down!  It was no surprise that she chose to illustrate it when she sat down with her journal.  [Admin Note :: As I was writing this, she peaked over my shoulder to say, “Oh. I’m not yet finished, Mom.  I want to color her, too.”]

It turned out to be a beautiful fall day and after our study, the kids enjoyed playing on the structures (the boys) and in the natural areas (the girls).  One family was new to homeschooling, so it was a delight to sit with the mom a while as the kids played to share our successes and failures.  She had many questions and I believe she left feeling much more at ease about her decision.

P.S.  This topic was selected from Barb’s Autumn 2010 Outdoor Hour Challenges.  To find out more about her challenges and how to integrate nature study into your curriculum, visit her blog, Handbook of Nature Study.

Aquatic Critters :: Summer Nature Study

We’ve been going to Indian Mary near Grants Pass every 4th of July holiday for nearly 15 years now. Each year, I spend a little time picking up the rocks along the shore and investigating the invertebrates that cling to the rocks. The past couple of years, since we are now “homeschoolers” we have gotten a little more scientific about our search and bring along tools for collecting. I hadn’t previously considered documenting our findings until this year.

rogue7Searching for aquatic critters is one of our favorite summer activities. The kids spent hours along the river rubbing the rocks to see what critters might fall off into the dish pan. We then carried this back to the campsite where we could sit in comfort of the shade to observe our specimens more closely.

In past years, I’ve always seen a number of dragonfly, mayfly and stonefly nymphs. Planaria worms have also been prevalent.  This year however, I didn’t find a single planaria and instead found numerous midge larva and leaches!  Quite a surprise.

Additionally, we discovered many translucent little gel-like bubbles attached to the rocks as well as a couple of white tissue-like cocoon shapes (shown below).  I am not certain what these are, however.

We pack along a few reference materials with which to identify our discoveries and to learn more about each specimen. Click on this link, A Guide to Aquatic Insects, for a free excerpt from Science Logic: Ecology Explorations.  Using these references, the kiddos and I spend some time sketching and taking notes in our nature journals.

As I shared our discoveries with friends and family with whom we were camping, it was brought to my attention that a notice had been posted near the restrooms that a health concern regarding the portability of the water had been issued due to the water turbidity.  Turbidity is the cloudiness of a liquid caused by individual particles or suspended solids that are generally invisible to the naked eye, similar to smoke in. The measurement of turbidity is a key test of water quality.

Using another key test of water quality, I was delighted that we had determined this for ourselves!

Wildflowers :: Summer Nature Study

Over the past couple of years, we have been loosely following the Outdoor Hour Challenges from The Handbook of Nature Study for our weekly nature studies. Though science – particularly ecology and life sciences – is my strong suit, I haven’t been very consistent.  When life gets hectic – nature study is typically the first thing omitted from our schedule.

As I tend to be more consistent when I am accountable to others and as there was a need in our homeschool community – I started hosting a weekly nature study outing using Barb’s Summer Nature Study: Using Senses eBook & the Outdoor Hour Challenges as guidance.  I had been doing this with our Roots & Shoots club on a monthly basis yet I hadn’t been consistent with nature studies independently each week.  Inviting others to join us on our outing assures that I don’t let life get in the way.

This week (our second week) the focus was on Wildflowers.  We spent the first 10-15 minutes undertaking a “Wonderful Wildflowers Scavenger Hunt” from NaturExplorers publication, Wonderful Wildflowers. This proved to be a great way to focus the group on the days topic and to engage learners of all ages and abilities.  We were able to find everything on the list except one (a flower growing among rocks).

After the scavenger hunt, we gathered around the picnic table and spent time sketching a flower of choice.  A few of the boys (my own included) opted to sketch a leaf or tree rather than a flower.  The above sketch is from Mei Li’s journal … her yet unfinished Columbine.   

Sketching their observations provides children with the opportunity to slow down and really “see” the specimen. It not only hones their observation skills but also unlocks creativity and provides a window into the past. I can’t wait to look back at these early journals when they enter college.

Best of all, the data collection process is backbone of quality science. It also reinforces important record-keeping skills such as reading, writing, and drawing.

Soil Erosion Experiment :: Science Saturday

As a part of our current unit study, we discussed the geology and soil composition of Africa.  Most of African soils are volcanic, meaning they are formed from rocks and ash that have been blasted out of volcanoes.  These soils are particularly rich in minerals.  Minerals are freed from rocks through erosion.

Depending upon the steepness of the slope, the kind of soil, and the amount of vegetation, different amounts of water soak into the soil.  After the water soaks into the soil, plant roots make good use of it.  If the soil is porous, some of the water continues downward until it accumulates in aquifers or underground rivers.

In the dry areas of Africa, there is usually too little vegetation to break the fall of rain.  During the wet season downpours, raindrops smash onto the bare soil, loosen particles, and carry them off the land, along depressions, down little gullies and into creeks and rivers.  Soil erosion is a huge problem in Africa and has been for a long time.  The accumulation of silt at river mouths can be a mile thick.

Over time, the chemical composition of soil may change as animals add their feces to the soil.  Soil can also move vast distances by the action of rivers.  The Nile River carries soil along its 4,000 mile length from the Ethiopian mountains and the East African highlands through Egypt to the Mediterranean Sea.  As the river water flows into the sea, soil particles settle and produce a great mudflat – a delta – spreading out from the river’s mouth.  Because the soils of the Nile Delta were so fertile, agriculture flourished as long as 12,000 B.C. and became the basis of the ancient Egyptian civilization.

Our Experiment

Question :: How does soil type affect the amount of runoff ?

Hypothesis ::  Each of the kids described what they expected to happen.  All were in agreement that they expected the sand to runoff the fastest, then clay and finally dirt.  Additionally, they all predicted that the grass roots would hold in the soil and absorb the most water, resulting in the least amount of runoff.

Materials :: 

  • 4 shallow boxes
  • 3 different soil types (we used dirt, sand, and clay)
  • Sod to fill one box
  • Scissors
  • 3 glass jars
  • Watering can
  • Water
  • Stopwatch

Procedure ::

  1. We set up each soil type in a shallow box.  In one corner of each box, we cut a V shaped notch.
  2. We filled the watering can with water.
  3. We set the box on an incline on a step with the glass jar positioned under the notch.
  4. Working with one soil type at a time, we allowed it to rain gently above and recorded the time it took for the glass jar to fill with water.
  5. We then set up a fourth box with grass and soil (essentially I just dug up various grass clumps from the perimeter of our yard and set them in the box – getting a little weeding done while we did our science lesson)

Data ::

  • Dirt –  1.20 minutes
  • Clay –  .19 minute
  • Sand –  .21 minute
  • Sod/Plants –  .53 minute

As the rain fell upon our ‘land’, we observed the formation of rivers, canyons and even waterfalls.

Conclusion ::

As we discussed the results of our experiment – comparing the water turbidity / clarity in the jars and the amount of sediment – we also made note of things that could have affected the outcome and made a list.

  • we didn’t have 4 boxes – and had reused one box with the sod (even though it was wet)
  • the dirt box was bigger and therefore there was more ‘land’
  • the sod was wet from the morning sprinklers and couldn’t absorb anymore water whereas the dirt we’d used (as well as the clay and sand) was dry

Building Toothpick Bridges .. a Lesson Plan

We have an opportunity this year to participate in our first homeschool science fair.  The kiddos have been fascinated with bridges for a long time so I knew immediately what project we’d undertake … Toothpick Bridges.  I’ll share with you my toothpick bridges lesson plan with you here.Buddy's Design

Capture Their Attention

Before we began construction, we read again the delightful picture book Bridges Are to Cross by Philemon Sturges.  We then used the internet to make observations of many modern bridge designs, particularly those we were familiar with here in Oregon as well as those we’d seen first hand in San Francisco.  I set up a little demonstration to show what structure was strongest … squares or triangles … using just drinking straws taped together at the corners to form a square and a triangle.

Strength in Design

I then gave the kids graph paper with which I instructed them how to begin designing bridges of their own.  They came up with several designs each – some of which weren’t feasible for toothpicks.  They then selected a design that would most easily be reproduced with toothpicks and we proceeded with construction.

toothpick bridge

Building Bridges with Toothpicks and Glue

In the classroom setting, I used to provide each team with a predetermined amount of money with which they would need to purchase their material … lumber (toothpicks) and welding material (school glue).  However, here at home, their imagination and thereby their design were the only limitations.

testing bridge strength

Testing Bridge Strength

We tested the strength of the bridges by suspending a gallon-sized milk jug beneath the bridge with a pencil.  Initially, we had used a smaller container but it turned out to be too small to contain the weights.  We then began to slowly add weights (marbles & metal washers) to the container.  When we ran out of weights, I began to slowly pour water into the jug.

toothpick bridge collapse

We continued in this way until the bridges finally collapsed or gave in to the pressure.  In the classroom, the eminent collapse and destruction of the bridges was always a highlight and was met with cheers and shouts of enthusiasm.  Here at home, I hadn’t anticipated the the big tears that we experienced.

toothpick bridge

In the end, the two bridge far surpassed our expectations.  Buddy’s design took on 16 pounds before it finally succumbed to the weight.  Sweetie’s design held more than 19 pounds!  Had she had more trusses along the roadway that supported the pencil, we hypothesis that her bridge could have supported more weight as her bridge remained intact with the exception of the road that gave way.

toothpick bridge

The kiddos are looking forward to presenting their experiment on Friday at the science fair.  Buddy is even talking about building more toothpick bridges – but he says he doesn’t want to test them.  “I don’t want to break my bridge.”

Engineering Marvels: Bridges

For more details and links to do this project with your kids, check out my Engineering Marvels: Bridges unit study.

Ponyo Inspired :: Science Saturday

My kiddos love the anime movies of Hayao Miyazaki .  One of their favorite is Ponyo which was recently released onto DVD.  This delightful Japanese film follows the adventures of a 5-year-old boy, Sosuke, and his burgeoning friendship with Ponyo, a goldfish princess who desperately wants to become human. After running away from and then being recaptured by her strict father, Ponyo — with some help from Sosuke — becomes more determined than ever to make her dreams come true.

Ponyo’s magic brings “to life” one of Sosuke’s toys, a candle powered steam engine boat.  Like most boys, my little guy was fascinated by this boat and asked about it frequently after we had seen the film on the big screen.  To his surprise and delight, he received one in his Easter basket this year.
Inside the boat and extending out the stern, there is a little metal tubes.  This tube fills with water and when the water in the tube boils, the steam expands. This pushes the water out of the tube. The reaction pushes the boat forward.  As the steam continues to expand, it encounters the section of tubing that used to be full of water. This tubing is cold, and the steam condenses back into water. This causes a vacuum to form, which pulls more water back into the tubes.  As it does this, a little putt putt sound is generated.

You would expect that the water moving back into the tubing would cause the boat to go backwards. However, the water doesn’t get very far before it hits the end of the tube where the two streams of water meet each other. Any motion caused by the water being sucked into the tubes is reversed by the water hitting the front of the tube and pushing the boat forward again.

Buddy has been having a great time navigating the seas of our bathtub.  I know it will be the first thing he packs when we go camping this summer.  Little does he know that he is doing science!  🙂

Click here for instructions on how to build your own candle powered boat.  Here’s another, for more detailed descriptions, Pop Pop!