Water

It is ubiquitous. It is essential. Without it, life as we know it would be impossible.

Water is a polar covalent molecule, which means that its molecules have a covalent bond that has a charge (polar). The hydrogen (H) molecules have a positive charge and the oxygen (O) molecule has a negative charge, while the whole water molecule (H2O) ends up with a neutral charge. This polarity makes water molecules attract other water molecules via hydrogen bonding.

The hydrogen bonds are weak, so as a result they are broken, and then made all the time. The bonds are broken through kinetic energy (motion). One way to increase kinetic energy is to increase heat. Hotter molecules move faster than colder ones, and as a result are further apart and less dense than their cold counterparts.

As water is heated, the increase of kinetic energy causes the hydrogen bonds to break and the water molecules will change their state from liquid to gas and enter the atmosphere as water vapor.

When water is cooled below 0°C, it changes states by freezing into a solid. Frozen water forms a crystalline structure. Snowflakes, famous for their beauty can only form because frozen water creates crystals. Ice and snow are less dense than water because frozen water expands due to how the hydrogen bonds are affected by the reduced temperature.

Since ice is less dense than water, it floats. This is a life saver for plants and animals because the layer of ice acts as insulation keeping the water beneath warmer, and the plants and animals unfrozen.Water also has a high heat capacity which means that it cools and heats slowly. Functionally, this makes water temperature much more stable than air temperature. This is why, even in the dead of winter, water will often be much warmer than the surrounding air, and even in the dog days of summer, water will be much cooler than the surrounding air.

Water’s high heat capacity is another feature that helps organisms survive the winter. By cooling slowly, the organisms are able to adapt and adjust their metabolism in order to conserve energy when food is less plentiful.

And this is just barely scratching the surface of water.

 

Sources:

Biology, Openstax

http://www.noaa.gov/stories/how-do-snowflakes-form-science-behind-snow

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CNX Free Textbooks

Any teacher worth their salt will continue working to improve and I like to think that I am worth my salt. What I have been doing lately is to research different teaching methods and strategies and then trying to incorporate them into my classroom.

However, I came across some content that I was supposed to teach that I was not entirely familiar with. So I started looking around and found a cool creative commons resource (Open Stax CNX) that is partnered with Rice University. It has numerous free and legal university level textbooks available for download. One book that I downloaded is searchable and has embedded hyperlinks, while the other is simply a color pdf version of the textbook. So, the quality varies, but it is hard to complain about free.

I found this to be especially beneficial because a university textbook is organized, like a textbook. Meaning that it was organized in a similar fashion to the textbooks my students use in class. This resource lets me find information that was significantly more advanced and in-depth than what my 6th-grade students will need to know. Helping me to learn, refresh, and be able to answer questions that curious students may have.

Pedagogical knowledge is not the be all end all. We need to know what to teach as well as how. This is one way to do so.

Check it out, and learn.

https://cnx.org/

This is simply a reflection.

Third graders are absolutely fascinated with magnets. Moving another object without touching it and turning a paperclip into a temporary magnet elicited ooh’s and aahh’s from both of my third-grade classes.

My students were engaged, asking good questions, and talking with each other about how magnets work. But even with that, I felt like my lesson was somewhat flat and had more style than substance. Looking back, I think that my students will remember what the magnets did, but how or why it happened. I think that this will be the case because of the language most students were using.

“The magnets stick together.”

“The magnets will get stuck to iron.”

“Wow, the paper clip is holding the binder clip!”

My students, with one or two exceptions, were not using the vocabulary words I thought I had taught them (north pole, south pole, attract, repel, magnetic field, etc). And, since they already knew what a magnet could do, I am not sure they learned much from this lesson.

I am not into showmanship for showmanship’s sake, and I feel that while my demonstrations were useful for the students, something was missing that would help the students connect the cool physical process that they were seeing to the unseen scientific facts that made it possible.

I think that the best way to make this lesson more valuable is to more clearly teach the vocabulary and then, make my students use and apply it in class.

Elaboration

Elaboration is a useful skill for students to learn. It is also a skill that helps students to learn. The primary way elaboration helps is by the connections elaborating forms.

As a teacher, there are many ways to get students to use this strategy in your classroom, or on assignments. One way you can do so is to have students answer how and why questions based on the key concepts/ideas you are teaching. Then, you can have students explain the relationship between the different concepts/ideas.

Then, as an extension to this, it is helpful to have students make connections from the content to their daily lives. This can be done simply by asking students, “How does this relate to your day to day life?”

By answering these questions, students will be organizing the content in their minds. This then makes it easier for your students to both comprehend and recall the information at a later date.

In answering these types of questions, students can use their class materials, but it is more helpful, if they attempt to answer the questions without looking first. Approaching the assignments in this manner will have the added benefit of showing the student what content they do not already know (students will need to be trained in order to do this effectively).

As teachers, I am sure that we include many elaboration strategies in each of our lessons, but do we make it explicit? I know that I do not often do so. So, instead of simply having students answer leading questions (how, why, etc), I am planning on having my students come up with the how and why questions on their own after I have modeled it with them.

The students will have a list of vocabulary words along with the key concepts of the particular unit. They will then need to create a diagram that shows and explains the relationships between the vocabulary words, and the concepts. Then, they will either include how it is related to their life in the diagram or they will write several sentences explaining how the content is related to their life.

For example, we are studying the water cycle in my 5th-grade science class. The key words are evaporation, condensation, precipitation, sublimation, and transpiration. The key concepts are how the water cycle works, and what affects the water cycle.

What I would expect from my students would be to draw a traditional water cycle that includes all the vocabulary words. Then, on the arrow that goes up for evaporation, students could write that temperature affects the rate of evaporation (hotter=more, colder=less). Something like this would continue for each step until they get to how the water cycle is related to their own life. Here, students would have flexibility. One student might write about how the water cycle helps plants grow. Another might write about how humans impact the water cycle by changing the environment.

For me, this blog is one way that I practice elaboration! I am working to connect various teaching strategies that I am reading about to my practice. Thinking and writing about how I am using, or will use each. And then working out how I can use the strategies together in order to maximize their effectiveness.

 

Sources:

http://www.learningscientists.org/blog/2016/7/7-1

http://www.mempowered.com/study/elaborating