Keeping Track of Lab Work

Yes, more on lab reports.  I don’t grade them right away, they just take a long time and I sometimes put it off for a week.  As a result, I get a bit confused about who was there and who didn’t turn in work and why.

I finally figured this one out, it has been the bane of my teaching existence for far too long.  Here’s the scenario:  I do a lab, tell them it is due in two or three days.  When I collect it, I don’t recall who was there that day, who worked, who just stood around, etc.  Now I’m missing lab reports, but I can’t recall if it is because they simply didn’t hand it in, they were out when it was handed in, or they were out and missed the lab.  In case you haven’t figured this out by now, paperwork is my downfall.  The solution that works for me is to create forms.

Excel to the rescue.  I made a form for lab day.  On the form I make note of who is present and who is out.  I also casually make notes on who is writing in their lab notebook or working on separate paper.  Some labs I want made up, others are a pain for me, so I exempt them if they were absent.

We’ve already been through the problem that I can’t attach excel pages on this blog, so I printed a pdf of one of the pages from my spreadsheet with my students’ names removed.  I have a separate page for each class so I only need to fill in the title, dates, and hit print.  I used this for the first time this week and I knew immediately who didn’t hand in work and who owed me work today because they missed school the previous day.  When I collect the work, I attach the form to the stack from the class.  For once, I am in control of lab reports.

Lab Attendance Forms

Lab Grading Sheet

If you grade labs, you probably struggle for consistency and simplicity in grading those beasts.  I know I do.  I’ve come up with a more simple plan through a series of iterations.

I make up these little score sheets, they run nine to a page.  The idea is simple; the lab is worth 25 points.  Each problem is a deduction of usually one or two points.  I grade on the score sheet, then staple or glue the sheet to the lab.  I find that the feedback of lost points gives them a clear indication of what to fix for next time.

I like a 25 point lab for a number of reasons.  I tell the kids, every lab starts at an A+.  Each point deduction drops the grade by one third of a grade.  So a one-point deduction drops an A+ to an A, where a two-point deduction drops an A+ to an A-.  This system lets me choose a value for a section, so if there is a lot of calculations and graphing in the analysis section, I can make omission of the work worth a full grade with a deduction of three points.  I don’t take late work unless they were absent, so not handing in a lab isn’t fatal, but it hurts.  A 25-point lab is also a good buffer for bad quiz and test grades.

I have played with this over the last couple of years.  My first lab or two of the year I grade holistically, I get a feel for what I think it deserves.  Then I go back and count where I would have given deductions.  That is why I know this works for me.  A lab that is in order and complete is an easy A.  I establish certain requirements, such as each page needs the header completely filled in, each section must be present and in the proper order, formulas and calculations are written out, and the last page is signed as an indication they did their own work.  As they get better at the layout and report, I can up the standards on the actual lab work.

The attached page is a pdf of my spreadsheet.  Use mine or make your own, whatever works for you.

Lab Score Sheet

As always, if you have ideas to improve upon this or do something you like better, I really want to hear about it.  I’m tired of having to learn all of this the hard way.

My Gradebook and Curving Algorithm

Here’s a little end-of-quarter gift for you.  I’ve been meaning to post my excel gradebook and curving routine for some time.  I think some of you are going to want to send me a Christmas present for this one.  (And if you are so inclined, I’ll give you an address to mail it to.)

The gradebook isn’t really all that special, it just does exactly what I need it to do.  The second sheet has a few sample grades so you can see how I use it.  In a nut shell, here’s the idea:

• A line for each kid, you can do first & last names, I tend to do last, first in case I need to sort.
• Along the top is the graded assignment.  I often use a comment in the field so I know what the actual homework was for that grade.  It’s helpful when they were out and need the assignments.
• The column marked “Point Adjustment” allows me to exempt the grade for someone that was out.  You can see the example on sheet 2.
• I have the kids give me a code, like their birthday or address.  Then when I go to print, I hide the name, sort by the average grade (decending), hit print, then undo, undo.  Don’t sort the first column.
• You will see some boxes at the bottom, two stacked and ####’ed out.  That is the average and std dev.  When I give a test or quiz, I copy and paste one of those to the bottom.  It lets me know how the trend is going.
• If a kid is failing or near failing, I color their line red.
• You can keep extra rows, but make sure the averaging function is removed or it will include those zeroes into the class average.
• A missed assignment can be blank, it still counts as a zero unless you do a point adjustment.  I normally don’t take late work, so I just put in a zero for those, but it’s useful for kids that were out to see a blank. It reminds them to turn in the work that was due.
• When the quarter is over, I make a copy of the spreadsheet and store it under admin archives.  Then go back to my original and wipe out all the grades and start over.

What’s great about this program is I can make changes quickly, I keep it on my USB drive, so grades travel with me, I print grades at least once a week, it’s very quick to post grades on my bulletin board, and the kids keep me honest if I mess up their grades – which in the end helps both of us.  It’s much faster than our school grade book program, so I consider my spreadsheet the master if there is a conflict.

Now, the curve routine.   After a test that will need curving (and don’t they all), I copy and paste just the grades to the sheet labeled ’stuff.’  Once there, I sort them high to low and then use the Average function and the Standard Deviation function.  I really only want the average, but the std dev gives me an idea how spread out the grade pattern looks.  I’m in a bullet kind of mood…

• Look at the grades and the average.  I like my test averages to be 75-77, but they are usually like 60.
• Go to the Curve sheet.  Go to the yellow boxes.  Here is where you get to play a little.  Take the highest test grade and make it what you want it to be.  If someone stood out from the rest, I may make it 100.  If not, 95 works for me.  Now the low – I usually start out with the low grade being curved to a 50.
• Go down to the single yellow box and enter your current average grade.  Below it, you can see what the average grade curves to.
• If the average is below what you want, you can boost the curves-to grade for the high score or the curves-to grade for the low score.
• When you have it where you want it, change the title on the Curve sheet and hit print.  It will print the curve, plus what the high, low, and average curve to.
• To enter into the grade book, I usually make a new column called ‘curve’ worth no points and put the delta in there.
• Pointer (worth and extra dollar or two) – use the comment function and put the curve numbers onto the test.  You can see this on the period 3 sheet on the test dated 11/10.  This way, if I have to go back and recreate the curve, it’s a piece of cake.

What I’ve found is that by keeping my test average around a C/C+, I have just the right grade distribution at report card time.

Ok, WordPress doesn’t allow uploading spreadsheets, so I saved it as a shared google doc.  Go and get it, do a save as to bring it to your computer.

http://spreadsheets.google.com/ccc?key=0AtZmpkiMp_0qdFVuODJJQVFlZWxfdHoxUS1OVzR1c3c&hl=en

This is a pain in the butt.  If you go to the link, click on file, download, and save it as your own excel file.  If you prefer, just email me and I’ll send you the file directly.  There’s got to be an easier way, I’ll look into it.

New Physics Forum

I got an email from Jeff asking me to promote his new physics forum.  It cracked me up because he called me an influential blogger.  Don’t influential bloggers get free t-shirts, or hot nerd chicks or something.  All I get is more papers to grade.  (As an odd side comment, and mind you, this was an after thought, I did a google search for “hot nerd chicks” and was quite surprised at the brilliance of my comment.  Who knew?)

I did say I would help him out and post a quick article and the link.

I think there is a place for his forum.  It’s actually what I wanted to do here along with this blog, but WordPress doesn’t make it easy and I need low maintenance to do this blog.

As of today there are only four questions, but I can see it growing quickly.

Jeff Hellman’s PhysExchange:  http://physicsteachers.stackexchange.com/

Jeff, you owe me a beer.

Predicting the Landing Zone of a Projectile

Let me start by saying that the kids really liked this lab.  It made them smile when they succeeded.

I kind of made this one up, kind of adapted it from the electronic timer manual.  The idea is that we use a ramp to accelerate a steel marble, have it pass through timer gates, measure the distance between the gates and calculate the velocity.  Do that a couple of times for accuracy.

Now measure the height of the table using a meter stick.  Use a fishing weight on a string to find the point directly under the edge of the table.  We now have the horizontal velocity, the height of the table, we can calculate how long it will take to fall.  Next we do the math and place a penny where the steel marble should land.

In the beginning, it would works sometimes, but not always.  I determined that our heavy epoxy table tops caused the steel ball to bounce, losing some of its horizontal velocity.  The bounce was easily dampened by placing two or three sheets of paper under the end of the ramp.  We also had some issues with hitting the side of the photogate.  Lining up the gates with the ramp was a minor issue, but an important one.  After the speed was determine, we moved the photogate away used the already calculated speed.

Here is the Lab as I wrote it up, it needs some updates like the paper under the ramp.  I realized later that I should have had the kids measure the starting height of the ramp.  Then we could go back to it later when we do energy and analyze the results.

Horizontal Projectile

Next year I think I will have them hit the penny first time, then a dime, then a small washer, so each time it must be more accurate.

As always, comments and ideas are welcome.

My Book Swap

I don’t know why I’ve never mentioned this before.  In my room I have a bookshelf full of mostly paperbacks.  The books are there for the kids to take, read, and if they chose, return.  I go to the public library every couple of weeks, they are constantly selling paperbacks at either 5 for a dollar or a bag for a dollar.  I must have about 200 books on my shelf right now.

I have lots of science fiction (Asimov, Bradbury, Clarke, Card), mysteries, thrillers (I love Ludlum novels), fantasy, even some non-fiction titles.  I have a bunch of the Sue Grafton series (“A is for Alibi”, etc.) since the protagonist is a woman detective.  I often recommend those to the girls.  I try to keep the books different from those they read in their English classes.  Books don’t equal homework.

I require nothing in exchange.  I ask them what they like, then I recommend something if I can.  Today a student took Stephen King’s Night Shift.  I pick up every copy of that I can find, it’s a great book and I recommend it frequently.

I even have one student who is constantly bringing in books her father donates to my library.

My goal is pretty obvious, get them to read something.  Anything.  If they are reading, they are learning.

I Need Help with Lab Reports

I’m the first one to admit I don’t know everything.  (Actually, I’m the second, my wife is the first.)  I don’t know how to proceed at this moment, I’m throwing it out there for discussion.

We are using the carbonless lab notebooks, I like them.  I want the students to use a lab notebook, but I don’t want the experience of learning to be about rewriting a procedure.  I’m struggling with the whole idea that every lab starts out with a hypothesis.  My personal experience of learning often begins with “I wonder what happens if …” You could say that is a form of a hypothesis, but it is really just a quest for understanding the workings of everything.

The other day we did a lab where we used a ticker tape recorder to make a mark every 1/60th of a second on a paper strip.  The goal is to record the changing distance of a falling object and the constant distance of a constant velocity toy car.  I wanted them to see a visual record of acceleration, to understand the distance changes at each tick, and to graph the distances over time.  They struggled to write a meaningful hypothesis.  How could they write one, they don’t know what they are going to see.  I wanted to help them, but I felt that if I said too much, I would be revealing the discovery they should be making.

If labs are about discovery, and I think they should be, then how can they have a hypothesis?  How is it discovery if there is only one right answer?  If I make the lab all about them finding the right answer, then their focus is on what will get them a good grade, and not about learning physics.  I’ve looked at lots of lab report formats online.  They make sense if the experimenter is doing research on a topic where he or she is actively working.  Each bit of learning leads to a new question and a new experiment.  Here, the hypothesis feels contrived.

Would it be wrong to have a hypothesis that is just a general question?  Am I going about this the wrong way?  I think I’d be happier if they wrote, “We are hoping to see visual evidence that differentiates a constant velocity and accelerating velocity.”  If I head this way, am I failing to preparing them for college?

One thing I am changing; in the future they can reference the handout.  It’s a waste of their time and mine when they have to rewrite my instructions.  Yes, it forces them to read the instructions, but that’s not deep and meaningful learning.  The clock is ticking.

What are you doing?

One Question

Their homework assignment was called “One Question.”  Their job was to write one science question that they wanted to have answered, any area of science is fine.  If they were goofy or tried to be funny they wouldn’t get credit.

What I got back blew my mind.  There were such incredible questions that I’m going to assign this about once a month.  I’m going to talk about some of these during science news days on Fridays.  Some of them I will save for when we get to the topic.  Some I will post as a list questions they can research and present for extra credit.

Extra credit is a sore point for some of you.  My rule on extra credit is this: if you are missing more than two assignments that quarter, extra credit is not available to you.  Extra credit is not an out for the lazy, it’s a boost for those who work hard and need a couple more points.

[I left the papers at school, I'll post some of the questions next week.  My own blog is blocked on school computers.]

I Hate Science Fairs

I hate them.

Parents hate them.  Most aren’t any more science literate than their kids.  The pressure on the parents to create a decent project is awful.  Coming up with a good science experiment project is really hard to do.  There are dozens of books on the topic and everybody is clawing at them, trying to find something they can handle.

Kids hate them. They see it as a grade, nothing more.  They don’t understand the need for the formality in the presentation.  All they know is they don’t win.  Now they hate science.

Teachers hate them.  Be honest, they are brutal to grade, the work is not worth the effort.  Please, no more volcanoes.

OK, now that I got that off my chest, let’s talk about this.

I love doing experiments.  I love inspiring kids to think.  I make my students experiment constantly.  I want them to play in science, find the joy and excitement.  I want them to ask questions and be curious.  I make them launch rockets and throw balls.  If they make a paper airplane in my class, they better make five or ten and tell me what design works best and why.  Is science really distilling everything they know about a topic and making it fit on a bent poster board?

I will be doing a science fair in my classroom in about a week.  Only I don’t call it that.  I call it my “Mythbusters Project.”  To be honest, I don’t care if it’s a stupid idea they are testing.  I want them to be goofy and have fun.  I help them to make sure they are doing good science.  I challenge their findings.  I make them work together and research.  I know, it’s not the county science fair.  So what?

You can’t sell someone something they don’t want or need.  Really, it’s true.  OK, maybe once, but you lost them as a customer forever if you do that.  Kids want to be creative, they want to think, they want to learn.  They are unbelievably curious.  If you don’t think so, leave a pile of mechanical puzzles on the table and don’t draw attention to it.  Every one of them will be in the kids’ hands in two minutes.  Try it.

Here’s the question you need to ask yourself:  What can I do to make this kid love science?

Science News in the Classroom

I was listening to my iPod this morning and I heard Neil deGrasse Tyson as a guest at a public symposium in Portland, Oregon.  It was published as part of the podcast “NOVA scienceNOW.”  I’m considering playing it for my class, it’s only 30 minutes long.

This sounds a lot like what goes on in my classroom on Fridays, only way more orderly and with microphones.  In my Conceptual Physics classes, my students have an assignment  on Wednesdays to print out a bit of science news, any area of science is fine.  They need to read the article and highlight key points.  I collect these and on Friday we have science news day, where we talk about anything science.  I use the articles as a starting point, and we quickly jump from topic to topic.  Nothing is off limits, they come up with a million questions.  Sometimes they go off and research something further from our discussions.

In addition to using this just to get them thinking about science, I use this to get across certain agenda items.  A couple of the news items were cut and pasted into word to make it easier to print.  I asked the kids to make sure they note the site it came from, I need the source so I can go back and read more.  We talked about good and bad sources.  Another student had an article on the 2012 predictions.  The first paragraph talked about some scientists needing facts, but the authors were going on “instincts.”  I did the pen and shoe drop, asking them about their predictions.  I emphasized that scientists guts can be a starting point, but facts are the only things we trust.

This week, an additional assignment is going to be to write a question about science that they have wanted to know the answer to.  I’ll may pick from those to get the conversation started or  I may put up a “great question” list and let them research a question and present the answer for extra credit.

I was going to imbed the podcast or attach the file for download, but WordPress wants me to upgrade from a free blog to do that.  Go to the iTunes store and search for NOVA ScienceNOW.  I tried the NOVA website, but they don’t make it any easier to link to the file.

Dr. Tyson has a couple of great responses.  One is about using his own children as an experiment in getting kids to be science literate.  It’s worth listening to for just that one.  There’s more, go listen.

After you listen to it, tell me if you would play it in the classroom.  I’m a little wary of audio only, kids tend to listen with their heads on the desks and it can be hard to get them back up.

Update - The kids enjoyed it.  At first, they were reluctant (no pictures), but I stopped it half way through and offered to switch to science news.  They asked in all three classes to continue the audio.  I know they like science news, so that was encouraging.  I think they honestly enjoyed the change of pace and learned a little something from someone else.

Getting Students to Draw the Problem

I’ve always found it challenging to get students to draw the problems.  I don’t understand their reluctance, I can’t imagine trying to keep the facts in my head, yet so many of them do just that.  The result is that they miss details and make mistakes.

Today I saw a simple problem that I thought I would use as an introduction to drawing problems.  The simple word problem says:

[Updated as used in class] There is a triangularly shaped park with trees along the edge.  There is a tree at each vertex.  Each side has five trees.  How many trees are there all together?

Very simple problem if you just draw it.  The answer is not 15.

Last Year’s Grades – Statistically Speaking

I don’t know about you, but I want the grades in my class to mean something.  I’ve seen so much grade inflation in schools.  It used to be school policy that we weren’t allowed to fail anyone.  Thankfully our new administration is so much smarter than the old one.  I certainly don’t want to fail any students, but if they don’t do the work and don’t try, I don’t have a problem giving them the grade they’ve earned.  Two students didn’t graduate because they failed physics last year.  I think that is a powerful motivator for this year’s students.  I will show them my grades distribution the first day of class.  They can decide how hard they are willing to work.

Here is the spread of my grades from 2008/2009:

• 7 – A’s
• 38 – B’s
• 35 – C’s
• 8 – D’s
• 2 – F’s

At some point I will put up a post about grades and how I curve.  I even have a spread sheet program that helps me.

Magic as an Introduction to Scientific Thinking

I love magic.  Being a scientist doesn’t take away from the amazement created by a well executed trick.  My father sent me a clip of Chris Angel doing a trick where he not cuts, but pulls a woman in half right on a park bench.  The trick is incredibly shocking, the people on the set are screaming in fear and surprise.  You can see they are visibly shaken.

YouTube video of Chris Angel. I’m going to show this clip and then start a discussion.  First question – did he really pull this woman in half?  Obviously that did not happen, so what did?  The students are going to either work alone or in small groups and try to come up with a way to explain and possibly reproduce the effect.

What I hope to get from this exercise is a little critical thinking.  If the woman was not pulled apart, and Chris Angel doesn’t have real magical powers, then it must be a trick.  We don’t know how he does it, but we can make educated guesses and then experiment to attempt to reproduce the method.

Optics with Jello Lenses

How do you see light’s path through a lens?  We did this experiment at the DAMOP teacher’s workshop at Penn State last year.  Make Jello in a flat bottom pan, about 3/4″ deep.  Use half the water so the Jello is firmer than normal.  You’ll have to experiment with the color and tell me which works best, I haven’t done this on my own yet.

Obviously the Jello is made the day before.  Now cut the Jello into the shapes of the lenses.  You can make prisms, double concave, convex, whatever you like.  You can float the pan in warm water to release the lenses from the pan.  Don’t do it too long, just enough for the Jello to lift out undamaged.

Now shine a laser pointer through the Jello.  You will be able to see the path of the laser and follow as the light is bent by the lens.  Set up a series of lenses and have fun.  When you are done, you can eat the experiment.

Anyone Teaching Robotics?

I’ve been searching for a curriculum and some ideas for teaching robotics.  I’m looking to build a course that is half a year of robotics and half a year astronomy.

I haven’t found very much so far.  Some stuff at Carnegie Mellon and constant links to Lego products, but not much else.  I’m looking to make this an elective the following year and I need to start figuring out how I’m going to make this happen.

Some of you must either teach this course or have someone in your school who teaches this course.

I need some help please.