Tag Archives: Biology

Alright, GO!

My grade 9’s are doing ecology first this year, and like last year, I kept the number of teacher-led lessons down to a minimum. But this year, instead of everyone working with invasive species, they are allowed to choose their own project (or projects, the number is unimportant) as long as it address the effects of human activity on ecosystems (one or many), water, and soil, and it must include one original hands-on investigation.

Since the investigation part seemed to be the part that was throwing them, the other day I told them that by the end of the 80 minute period they had to submit a description of what, exactly, they intended to do as an investigation, where and when they would perform it, and what specifically, they would be looking for (qualitatively or quantitatively).

I then told them we had a set of microscopes, dishes, jars, pond water, random soil samples from around the school, and a few litres of simulated acid rain. And then I said “alright, GO!”

I was pleasantly surprised by the inquisitive chaos that ensued, and by the end of the class I had detailed descriptions of most of the investigations, as well as at least a dozen experiments actually under way.

It was a frenetic, chaotic, inquisitive class. As a science teacher, I couldn’t have been happier!

Real EdTech, Part Deux

Yesterday I posted about using portable everyday technology to do simple but spectacular things.

But wait, there’s more!

One of my students was with me in the library two days ago when I posted the microscope video on YouTube. Not only did he subscribe to my channel and post a question about what he was seeing in the video, he also told his friends about it. So when we did the activity in class the following day, almost everyone brought smart phones and wanted me to show them how to do microscope videography.

How cool is that?!

Real Educational Technology

I have mentioned before how I became a convert to smart phones – indeed, I have become a full-fledged cyborg with mine – and I still keep finding new ways to use my iPhone for education.

Just today I got so excited with what I was looking at under the microscope I decided I had to share it. So I whipped out my phone, captured a bunch of clips, edited them, and then posted the result to facebook and YouTube, all from the phone. Now THAT is real-world, authentic educational technology.

Enjoy:

(PS – go full screen. It’s high res!)

Check Out Project Noah!

 

I’m not sure why it took me so long to discover Project Noah. It is a citizen science community that, in their words, is intended to be “a fun, location-based mobile application to encourage people to reconnect with nature and document local wildlife”. Essentially, you take pictures of animals and plants, and upload to the Project Noah website. But it is based around smartphones. With the app installed on your iPhone or Android, users can snap anything interesting (or mundane, too) and upload. You have the option of identifying what you have uploaded, or requesting identification. The location information can optionally be attached to help learn more about geographic distribution. There is also a social network for chats and discussion, and even patches for accomplishments.

The images and locations are searchable online, so it can be used by amateurs and researchers alike, and as they say their “ultimate goal is to build the go-to platform for documenting all the world’s organisms and through doing this we hope to develop an effective way to measure Mother Nature’s pulse.”

I uploaded my first image today of a snail (me: “Oh! Gotta take a pic of this snail!” My wife: “Geek”),  and I took the time to double check the identification and enter that information. I think there is potential for this to be used in the classroom in many ways – an image resource, a class project or hands-on biodiversity lesson. Having to take a few minutes to identify and classify what has been found is an extra layer of analysis and engagement which requires a bit of patience, but pays off.

Of course, now that I have my first upload, I’m hooked. And, as with my snail picture, I expect to be called a geek a lot more often…

 

End of Term Quickies

Because of the vagaries of the calendar, school goes late in December this year. As a result, everyone is frazzled, and a not insignificant number of students have already left for the holidays*. As a result, I needed to come up with things that would be meaningful, but not indispensable. And fun – partly to keep the kids engaged, but also, maybe just a little, to make the early vacationers a touch jealous. So here are some of the things I did:

1. With my Grade 9’s, since we are working on the Chemistry unit, we did a Great Periodic Table of the Elements Bingo Scavenger Hunt! And yes, the exclamation mark is part of the title. The class is divided into teams of three or four, and each team is given a large periodic table and a bingo marker. The rules are:

  1. Each team will collect items (or photos of items-see #6 below) that contain a particular element. Note that the element must be prominent or significant in the item, not merely “traces of” or contamination.
  2. Each item will be confirmed by the teacher as containing that element, which can then be marked on the periodic table.
  3. After one hour, the team that has collected the most elements wins.
  4. Even if an item contains multiple elements, that item can only be used for one. In other words, one item (or multiple identical items) cannot be used for multiple elements. In addition, items that are physically collected cannot be shared between groups.
  5. When collecting items, you must have permission for each item.
  6. If an item cannot be moved, or you do not have permission to collect it, you may instead take a photograph, but one of the team members must be in the picture.
  7. You must be quiet and respectful in the hallways. If you make noise or are disrupting in any way, you may be removed from the game.
  8. Only those items (or images) returned to the classroom within the allotted time are counted.
  9. Good luck!

It took up a full 80 minute class, the kids had fun, and they even learned a thing or two. During the final class, my colleague and I did a few chemistry demos – stoplight reaction, zinc and sulphur combustion, Marge’s Hair (natural gas bubbled through bubble solution), and an alcohol pulse jet. End with a bang!

2. With my Grade 10’s, they are working on something a bit more involved: stop motion animations of mitosis. Some are doing old-school flip-book style, some are doing a rapid sequence of powerpoint slides, and some are doing flash. One used pasta. Awesome.

3. With my 11 Biology class, we did a timeline of evolution. I came across this tutorial  for creating an interactive timeline using scripts and a Google Docs back end. It takes a little bit of prep work, and you have to be familiar enough with RSS feeds and HTML to get it working, but it is quite effective once the bugs are ironed out. Each student was given a person on whom to produce a brief bio (background people mostly – Buffon, Cuvier, Lamarck, Linneaus, Smith, Malthus etc.), which they submitted using a Google Docs form, and it then automagically showed up on the timeline. Because the timeline page uses third party scripts hosted elsewhere, they can have a copy of the HTML file on their local machine which shows the live data.

Merry Christmas, joyous solstice, happy Hanukkah, or whatever you celebrate have a peaceful holiday, and a happy New Year!

 

*they justify this by saying “we don’t do anything in the last week”, and of course we can’t do anything in the last week, because half the kids are gone.

 

A Digital Analogy for Transcription and Translation

I have often referred to DNA as the cell’s “hard drive” – it is an information  storage medium, but does not itself process the information. Recently a student in an introductory course asked how that information is used, so I extended the digital analogy this way:

On your hard drive, information is stored magnetically. The direction of the magnetic field designates a binary coding system of 1’s and 0’s. So let’s say the following sequence is stored on your hard drive:

01010100010010000100100101010011001000000100100101010011001000000100 000100100000010100000101001001001111010101000100 01010100100101001110

This information can be copied to a flash drive, where it is still stored as 01010100010010000100100101010011001000000100100101010011001000000100 000100100000010100000101001001001111010101000100 01010100100101001110, but there is a subtle difference. In the flash drive, it is not stored magnetically. It is stored electronically. So the same information is copied (transcribed) to a slightly different medium, just as the information on DNA is transcribed to mRNA.

Now we can take that same information on the flash drive, and send it to the printer. The printer will receive the string of 1’s and 0’s, interpret them, and then spit out a piece of paper that says:

THIS IS A PROTEIN

The printer translates the binary code (1’s and 0’s) to ASCII code in the form of letters, the same way a ribosome translates the mRNA code into amino acids and polypeptides.

 

A Foray into “non-traditional instruction”

This year, with the Ecology unit in my Grade 9 Science classes, we focused heavily on invasive species. So after seven weeks of class (we have each class every other day), I think I gave a total of 4 traditional lessons. Instead, we researched invasive species in Ontario, hiked into the park adjacent to the school to locate, identify, and map out the extent of invasive plants such as buckthorn, dog-strangling vine, Norway maple and European reed. We did further research on why these things are a problem, and then (with, I’ll admit, just a bit of prompting) the students discovered that local garden centres are selling several plants that are on the official Ontario invasive species list.

So we decided to do something about it. The students have been writing letters, and then peer-editing, and compiling and synthesizing the best bits into group letters, which I then went over with them in a serious way to ensure the message was clear, the tone was appropriate, and the information was factual. During this process several students asked “we’re not really going to mail these are we?” To which I replied there is no point in writing them if we aren’t going to mail them. Knowing these were now “real” letters, and not just mock letters for my benefit, got most of them working to make sure they were of high quality.

They are composing letters to the city councilor, the mayor, the parks department, the provincial Ministry of Natural Resources, the Minister of natural resources, the premier, the local MPP, the local federal MP, the federal Ministry of the Environment, and the CEO’s of the major garden centres. If we don’t get at least a couple of responses, I will be disappointed.

We have spent as much (if not more) time talking about the importance of a well-structured argument, the tone of a letter, conciseness, how to edit, and how to find out who to send letters to as we have on community interactions and nutrient cycles. And yet, this holistic approach hit as many of the curriculum expectations – though not as explicitly – as a series of lectures would.

For a unit assessment, I decided to go with two things, a poster where they can “brag” about the action they have taken to help with invasive species, and a portfolio of sorts. This is what I have asked of them to demonstrate what they have learned:

The Portfolio must include an item (either works or notes you have produced, or items that you have found) and an explanation of how that item can be used as evidence for each of the following open ended questions. The explanation part for each should be at least a few paragraphs – you are, after all, trying to convince me that you learned something:

  1. Something you learned that you found interesting or surprising
  2. Something you were particularly proud of learning, producing, or creating, or something you found particularly challenging
  3. What you learned about the dynamic nature of ecosystems
  4. Something you learned about the impact of human activities on the sustainability of ecosystems

I don’t know quite how I will evaluate this yet, I think I need to have the students help me with that. We’ll see how it goes.

It was kind of strange teaching like this, I’ll have to admit, but rewarding for the students (well, the ones who have taken it seriously) and me. I liked doing something real, and having the kids see for themselves the extent of invasiveness. But the sad thing is now we will be switching topics, and I have no idea how I can do something like this for the basics of atomic structure and the periodic table.

 

Mitosis lab as the basis for a discussion of error

We were doing a lab in Biology the other day. AP Biology teachers will be familiar with it, but the basic idea is that students count the number of cells of each phase in the meristem of an onion root tip using a microscope. By using the count of each phase, they can estimate the percentage of time each phase takes. At 400x, there are typically about 250 or so cells in the field of view, and the phase of each cell is not always certain, so it is not a trivial task. With care and patience, however, results can be pretty good. My students were quite confident with their counts. And, in truth, their combined data provided values that were not at all bad.

But here’s the interesting part. I also gave them a sheet with a couple of these images (click to enlarge), and asked them to find and circle one example of each phase.

And, collectively,  They did really poorly. Few of the students could correctly identify three or more phases. And yes, these are photos of the same microscope slides they were using.

I am still coming to grips with the ramifications of this discrepancy, but some of the conclusions are:

  1. Students’ confidence in their ability is not always a good measure of their ability
  2. This mitosis activity is is fairly immune to error
  3. Sometimes, biology can be harder than it looks, and it is NOT about memorizing
  4. Real life doesn’t look like the picture in the textbook.
  5. This is an excellent exercise to highlight and discuss points 1-4 above with the students.

One added observation – while the students were not all able to identify the phases of mitosis, they did notice instantly that they did not have the same images as the person next to them. Hmmm.

Simple analogy for homologous chromosomes

I am teaching Grade 11 Biology this year for the first time in seven or eight years, and quite enjoying it. One thing about doing a course you haven’t taught in a while is the joy of going back through your old notes and resources – it’s a bit like reading your old diary entries. There’s a bit of nostalgia for things you remember, and excitement at finding things you had forgotten.

In this age of computers, I sometimes forget how I used to explain things without having a zillion graphics and animations at my fingertips. One such explanation was for homologous chromosomes and the concept of alleles. I find that, despite the simplicity, many students have difficulty with the terminology and with conceptualizing genes and alleles. So the analogy I would use is clothing. I would have two students (ideally of similar height) represent a homolgous pair of chromosomes. Each “chromosome” has a gene for shoes, for socks, pants, and shirt. But the alleles may be different – one student might have the Doc Martin allele of the shoe gene, while the other has the All Stars allele. They might both have the blue jeans allele for the pants gene, and so on (of course, now I work at a school with student uniforms, so I have to compare my clothes to theirs to get different alleles).

It is a simple, low tech demonstration, but it seems to be quite effective at getting the point across.