Mystery Minerals

During our minerals unit, we read a section about the physical properties of minerals.  The hardness, streak, luster, specific gravity, cleavage, fracture and special properties of a mineral can be used to distinguish it from others that may have a similar appearance.  As a lab to complement this lesson, students performed several tests on four "mystery mineral" samples, then had to make hypotheses about the identity of each. 

To prepare for the assignment, I created mineral identification kits that included a magnifying glass, a streak plate, a piece of copper, an iron nail, a magnet, and a piece of glass.  Because I grouped each class into four groups, I chose four "mystery minerals" to rotate around the room.  I chose to include gypsum (for its unusual softness), sulfur (for its unusual appearance), sphalerite (for its unusual reaction to hydrochloric acid), and chalcopyrite (for its sparkly, metallic luster).  Later on, we included some samples of calcite just for fun.

Students received a lab packet that walked them through the tests and observations that needed to be recorded.  Each group made observations and sketches about the appearance, luster and texture of the minerals.  They also performed a streak test on the mineral with the ceramic streak plate, as well as a hardness test with fingernails, pieces of copper, iron nails, pieces of glass and ceramic streak plates.  A final section of the packet required that students look for other unique properties, such as magnetism, residue/greasiness, and chemical reactions with acid.

For obvious safety reasons, we performed the acid tests as a whole group with adults applying the hydrochloric acid to the samples.  For sulfur, gypsum and chalcopyrite, there is no real reaction or effect when the acid is applied.  Sphalerite, however, creates a very noticeable rotten egg odor when hydrochloric acid is applied and it will eventually dissolve if enough acid is used.  At this point, we added samples of calcite to the mix because they actually fizz with just a few drops of acid. 

At the end of the testing phase, I created a chart, shown below, with the officially recognized geologists' data for each mineral.  Students then compared their results to the results in the chart and tried to match each sample to its true identity.

I'm not quite sure why, but this is always one of my favorite labs of the year.  We may do many active lessons in this class, but this one really feels like "real science" to the kids because they are using real scientific tools and materials to find real scientific data.  At this level of science, most of the so-called "labs" that we complete are really just demonstrations or models, but in this case, it just feels more inquiry-based.  Best of all, it can be completed with just a few common objects and a box of mineral samples from your typical school supply catalog!

How many points is your name worth?

Today in math, we took a break from our usual routine to complete an activity related to our most recent unit on lines and angles.  The basic idea was to measure the angles in the letters of a name and to add them up to find a point value.  At first, we made predictions about whose name would have the most points, but many of results were quite surprising. 

To prepare for the activity, I created simple posters of each student's name on 11" x 17" paper.  I used the most angular, sans serif font that I could find - Century Gothic.  I also created an example with my own name to demonstrate the concept to students.

Each time a student found an angle in his or her name, they marked it and measured it with a protractor, then labeled them.  At first, students found just the obvious angles in Ms and As, but as the scores got higher and higher, students searched for more angles to increase their scores and remain competitive. 

Overall, the activity was perfect for a 45 minute class period and was a nice wrap-up to our unit on Lines and Angles before the study guide review and quiz.  Who knows, maybe next time, we can expand it even further to include identification of types of lines...

Modeling Mitosis

Mitosis is a confusing process if you learn about it without context.  When you think about it critically, however, each step has a clear purpose.  In order to improve our understanding of mitosis and how it occurs, we decided to model it live in class.

Each student was assigned a role as either cell membrane, centriole, chromosome, or nucleus.  In our class, we have 10-11 students, so we selected one nucleus, four students to help with the cell membrane, three students for chromosomes and two centrioles.  These numbers can be adjusted as needed, or several cells can be modeled. 

At first, we set up a "cell" on the floor with jumprope acting as cell membrane, a large laminated paper disc as the nucleus, laminated pictures of centroles, and chromosomes.  The chromosomes were also made of laminated paper, but I created them so that they velcro together on the centromere and can be pulled apart during a later phase.

(I made several colors of the model below.  I cut them out, then put velcro dots on the centromere so that they can connect together, then tear apart when necessary.)

Once students were sorted with their roles and had their handouts showing the phases of mitosis, we began our simulation.  First, the genetic material in the nucleus bundled together into chromosomes.  The centrioles then move to the far sides of the cell and begin to form spindle fibers (modeled by yarn) that extend towards the nucleus.  As the nucleus dissolves, the chromosomes line up in a row in the middle of the cell.  Each spindle fiber grabs onto one half of a chromosome, then pulls the halves of the chromosomes over to the sides of the cell.  At this point, two nuclei form in either side of the cell and the cell membrane students begin pinching in and creating two separate cells. 

We had to practice this a few times in order to get it right, but after a few tries, we were able to go through the whole process with little direction from teachers.  Overall, it was a fun way to get up out our seats and model a process in action!

Growing Crystals

In our book, it describes two ways that crystals can form from solution - when water evaporates and leaves the mineral ions behind, or when the solution is so concentrated with dissolved ions that they form in the solution.  We decided to model these two phenomena in our classroom in the simplest way - by showing salt and sugar crystals.

Salt crystals are incredibly easy to show from solution and they look pretty striking when they are done.  For our demonstration, we mixed a solution of salt and warm water, then simply poured it into a shallow pan.  As the water evaporates away overnight, the slow process allows the salt ions time to re-connect into cubic crystals.

Depending on several variables in the solution, the crystals can be tiny cubic growths, or much larger.  Below are some images of both smaller and larger crystals.

Demonstrating crystals forming in solution is a little trickier.  We decided to make rock candy in the classroom.  In a pot or saucepan, mix two parts sugar to one part water and bring the solution to a boil.  This is the only way to ensure that the sugar is completely dissolved.  We used a simple lab burner to do so.  Once the solution has boiled, you can suspend either a string with a weight on the end or a popsicle stick into the solution.  We created a cross-shaped apparatus out of two popsicle sticks and a rubber band to make sure that the stick did not touch the bottom or get stuck to the sides. 

The salt crystals are typically ready overnight depending on the depth of the water.  I will usually move onward with whatever lesson is scheduled for that day, then allow the students a few minutes at the end of class to analyze their salt crystals and record some data into their lab packets.

The sugar crystals typically take 4-7 days, but some small crystals can be seen in those first few days.  Students will also do the regularly-scheduled lesson for that day, then record their observations on the last day of class.  Technically, these sugar crystals are edible after a quick rinse and a few minutes to dry.

Often, the sugar crystals can be a bit tricky and tend to form along the sides of the cup or beaker more so than along the stick or string.  Either way, crystals will form and they are typically large enough for the kids to pull them out and examine them.  Below is an image of sugar crystals that formed predominantly along the inside of the cup.

Wonders of Wordle

When I first heard about Wordle.net, I thought that it was a really cool concept, but I wasn't sure exactly how I would incorporate it into lessons.  Below I have described some of the lessons that I have designed using the website.

Wordle is a website that takes text from any source and converts it into a visual representation of the text.  It analyzes it and makes the size of the word as it appears in the "wordle" is proportional to the number of times it is used in the text.  You can either copy and paste text from another source, or you can list the URL of a website or blog and create a wordle of that text. 

First, Wordle will generate an image that features a randomly-selected combination of fonts and colors, but all of these things can be customized.  Wordle is also smart enough to restrict frequently used words like "and" or "the" and just use more meaningful words and names from the text.  Finally, once the wordle is generated, you can customize it and remove certain words. 

Below are some examples of how teachers all over the country have used Wordle.

This student copied and pasted the entire text of the United States Constitution to create this wordle.

This Wordle uses a research paper on the history of Japan as its source material.

Instead of copying and pasting, you can also list a URL and the site will pull all of the text from that site.  Just for fun, here is a wordle of my blog.

Back to business, we used wordles in our reading class this week and it was quite successful.  We are half-way into Cornelia Funke's The Thief Lord, and the plot is really beginning to thicken, so I thought it was time to reflect on what we had already read to revisit the build up of suspense.  Each student was assigned a chunk of pages from the past 25 chapters and reread it to refresh their memory. 

Once they had reread the passage, students wrote a two-paragraph summary of the events in that section.  We copied and pasted the text into Wordle and created images of the summaries.  We printed the summaries and each student wrote their name on the back of the wordle.

Each student received a slip of paper with the names of each other student in the class.  We silently passed the wordles around the room in a rotation and tried to pinpoint the exact moment in the story that the wordle described.  As they came up with their guesses, they recorded them on the slip next to each students' name. 

At the end of the activity, each student was invited to share their wordle with the class, then take their classmates' guesses about which scene they described.  The students' guesses were mostly accurate, but we found that this was significantly more challenging than the similar guessing game we played with text-rendered poems earlier in the year. 

All in all, it was a successful experience, and it also got the students used to the workings of Wordle.  We can use this website in the future as a writing aid, for finding over-used words, a summarizing tool, for finding main ideas, and as a fun way to visualize text from all subjects. 







I bet if I made a wordle of this post, the word "wordle" would be really big...

Inspired by Inspiration

Have you checked out the software Inspiration?  It's definitely worth a look.

We are fortunate enough to have this software preloaded on all student and teacher laptops, but many of the kids still do not know how to use it.  Inspiration is a software that allows you to type information into graphic organizers or webs.  There are several different options for these bubbles, as well, including shapes, images, colors and formatting. 

These webs allow students to visually organize information for practice when worksheets or more traditional study methods have become tedious or ineffective.  There are also tons of templates preloaded into the software for common topics in reading, math, science, social studies and music. 

Earlier this week, we tackled the topic of cells, tissues, organs and systems, and to me, this subject matter needs visual organization for it to make sense.  To display this idea, we created webs of six of the human systems (digestive, respiratory, circulatory, muscular, nervous, and skeletal) and mapped out their parts (organs) with images of the cells.  This way, students had an electronic document showing the diverse appearances of different human cells.

We have used these kinds of webs in reading and science with much success.  What is even more exciting, however, are the potentialities for writing.  As long as the web bubbles and links are formatted correctly, Inspiration can take the web and convert it into an outline.  This outline is printable and can also be copied into Microsoft Word for crafting essays and paragraphs.  Get inspired!

Mitosis Virtual Lab

We've already dragged out the microscopes a few times during this cell unit, but it would have been quite a feat to get them out again and find just the right sample with cells in the process of mitosis.  Instead, we conducted a virtual lab online to view actual cells in mitosis and identify the stages. 

As is the routine in all of our labs, students had to maintain a lab packet, follow the scientific method and answer reflective questions, but the inquiry itself was occurring virtually on screen.  Students were provided with a link to Rutgers University's online biology labs and completed Lab #2 on Cell Reproduction. 

During this lab, students viewed a sample of plant cells (onion root tip), as well as animal cells (whitefish blastulae) and identified the stages of mitosis.  They also had to reflect on the differences in the stages in each sample.  Also important, students always must make sketches of what they have seen in order to properly visualize the concept or task at hand, and also to look back to in their science journals for reference. 

Finally, after completing the steps of the virtual lab, they answered thoughtful and inferential questions in their packets designed for them to draw on their knowledge and reflect on what they have seen.  The packet that we used is shown below:

Yesterday was our first attempt at a true, independent virtual lab and it was very successful.  While I value the experience of preparing slides and looking through scopes at real samples, virtual labs are a great way to capture particular events or processes in a cell that might otherwise be missed in a classroom-prepared slide.  Virtual labs are also particularly important when supplies are limited so that students can still see and experience the concepts rather than just reading or hearing about them.  Particularly when we delve into the physical sciences, it can often be difficult to model certain natural phenomena in the classroom and I look forward to incorporating more virtual labs into the curriculum.