Teaching: Finding Good Problems

I am a lowly teaching assistant, but since I have taught my particular class (Introduction to Electromagnetism) now four times, the professor in charge of the class has given me a great responsibility--to choose the problems we teach to the students.

I love this responsibility. I love to pick a variety of problems, ones that will demonstrate a key point, or one that will spark the students interest in the topic. There's just one problem. The textbook we use does not share  my philosophy. I pulled out my old text to compare. The book I learned from had 50 - 60 problems per chapter, with not very many that were repetitions. The book is thin, but dense, and well written. It has simple diagrams, and no web links.

The textbook I now teach from is more than twice as thick, but does not cover as much material, is full of pictures and QR codes, and although it has about a hundred problems per chapter, they really only have 3 or 4 problems per topic and then repeat with new numbers or a slightly different configuration. Yes, people learn by repetition, but the writers ended up not giving the students anything really challenging, and they (the students) get bored. With a few exceptions, their idea of a hard problem is to reference a famous experiment, simplify it immensely and make an 8 part problem that isn't actually any harder than doing 4 normal problems. The book rates its problems as *,**, *** problems, with *** being the most difficult. There are entire chapters without a *** problem. And a * problem is plug-n-chug. This is frustrating for me, but also for my students, who know when they are seeing the same problem over and over.

Due to a scheduling fluke,  I was given the opportunity to teach some supplementary sections on two topics. I told the professor that I wanted to use problems from some other resources, and he agreed! I've been having a blast looking through my old notes, especially since I can now appreciate all the work that my professor did preparing for class. And my students, with one section down, seem to like being challenged, but in a way that they feel they can actually succeed.

I can't wait til I can choose the text, as well as the problems. Reasons to pass my qualifier and get my PhD.

Jogging, Day 4

So week two of my jogging experiment began, despite threatening rain. The plan I had worked out over the weekend was to run 5 houses, walk 3, repeat for the 2 miles. My idea is to keep shifting a house from the walking portion to the running portion until I'm just running, and then increase the length of the run. Weirdly, my legs seemed to ache from not-running on Sunday, so I wasn't sure what was going to happen today.

It was fine. My legs were feeling it by the end, and after 5 houses I was a little winded, but I was ready to go again after walking for 3. And again, it felt good. I don't get it. I've never enjoyed exercise that wasn't long distance walking in my life. Maybe because I'm doing it at my own pace, instead of a pace someone else set? Setting? Penny? Instant reward? No idea, but I'm going to run with it (pun completely intended)

Another plus--Penny was tuckered out  by the end, but not before. After doing our usual post-jog routine of water and frozen blueberries, I went to my study to write this (and then study), and she came up stairs and fell asleep.

She likes to sleep on blanket piles when I have some to spare.

She has a sixth sense for when her human is taking pictures of her. She'll wake up enough to give me a look, and then goes straight back to sleep.

One ear just a little more alert for camera noises.

Apple Butter Muffins

When I woke up this morning, I wanted muffins. It happens, especially on the weekends. As I puttered around making coffee, I decided that what I really wanted was applesauce muffins, like my mom used to make. But I didn't have apple sauce, and I didn't have her recipe, which I couldn't use anyway since it would use white flour. Time to be inventive.

I didn't feel like dealing with the fussiness of my totally-from-scratch muffin recipe. I decided to gamble on retrofitting the muffin recipe out of my Better Homes and Gardens cookbook, and use some apples-only apple butter I had in the fridge as both the apple sauce and the sugar.

This is what it produced:

Hello, delicious

It produced a muffin that did not collapse. That had the texture of a muffin. That had the taste of an applesauce muffin, without any sugar or artificial sweetner. That browned nicely.

Most importantly, it produced a muffin that my husband continued to eat through out the day to the point when I had to ask him to leave me some for breakfast tomorrow. I made a dozen. There are 2 1/2 left. Most were eaten by my husband who hate healthy hippie food. THAT, my dear readers, is called success. 

Apple Butter Muffins

1 2/3 cup fine oat flour

1/3 cup almond flour

1 tablespoon baking powder

1/4 tsp salt

1 tsp cinnamon

2 large eggs

1/2 cup unsweetened apple butter

1 cup milk

1 tsp vanilla

Sift together dry ingredients in a large bowl. In a separate small bowl, beat eggs. Add apple butter, milk and vanilla extract and whisk to combine. Form a well in the dry goods,  pour the wet into the dry and whisk thoroughly to combine (overbeating is less a concern with oat flour). The batter is going to be thin. Ladle into greased or lined muffin tins, and let sit a minimum of 20 minutes (you can easily make this the night before, and just pop into the oven when you get up). Bake in a 350 F oven for 30-40 minutes, until muffins are springy to the touch and a toothpick comes out cleanly. Let sit 10 minutes before eating.

Meet Penny

I have mentioned our dog, Penny, before, mostly in my jogging posts, but I feel the time has come to formally introduce her. Also, it gives me an excuse to use some of the picture's I've collected of her.

Penny is a terrier/chihuahua/who-knows mutt, who, we think, is about 2 years old. We rescued her from a local humane society, who in turn had rescued her from the street. She jumped out at us among all the other dogs at the shelter because she wasn't barking, and she wasn't really jumping at her crate either. She was just looking at us. Also, she was small. The first dog we took out was a year old untrained lab, and it took the two of us to control him. This dog, who they had labeled "Chiquita" I could control no matter how much she wanted to chase a squirrel. We got her the next day, which gave us a chance to buy appropriately sized dog things.

This is what she looked like the day we got her:

She was a skinny little thing. She weighed about 13 lbs in this photo, and at this point the vet said she needed to gain about 20% to be healthy. According to the shelter records, she weighed 11 lbs when they took her in. I can't even imagine how wasted she must have been. 

This is her today:

My darling husband helped me get her to pose properly 

She's now about 17 lbs of muscle and energy. It took a long time to get her to fully trust us, and for us to really see her personality. She started out very timid, afraid of everything, and so weak she couldn't even hold her rope toy. Now we have to try to protect her from her own curiosity, and she'll rip the rope right out of your hand if you aren't careful. 

Penny is my first dog. I grew up with cats, which are wonderful pets, but are not dogs. So its totally possible that all dogs are like this. But I am delighted and amazed at how cuddly she is, and how much she seems to want to be near us, whenever we are home. If we are watching tv, she'll play tug-o-war, sleep on her mat, or chew her rawhides at our feet, unless its cold, in which case she will curl up as close to you as she can. 

I mean, find the six inches of space between you and the sofa arm, curl up next to you.

If I am cooking, she'll observe from a comfortable spot where she can spring into action as official kitchen spill cleaner-upper. If I am doing research or homework, she'll quietly sleep under my desk or in her soft crate. If I get up to move, she'll follow. 

More over, she is a clown. And I will swear she does it on purpose. She will chase her tail and do little floor gymnastics if she thinks you are stressed, or sad, or not paying enough attention to her when she wants to play. Sadly, I have never successfully captured this behavior. 

I realize that the internet is full of pets. But playing around with my dog and making food are about the two lightest things I do with my life, and I can already feel this blog tending to the serious. But I want to post about happy things too, and I can post pictures of my dog, knowing she can never protest.

~PhysicsGal

Jogging, Day 3

Today completes my first week of jogging. Yay!

I confess, I almost didn't try to day. It was hot. I was tired. My legs were still a little sore from Wednesday and walking 6 miles in the heat yesterday. "I'll do it Saturday" I tried to tell myself. "No you wont." myself countered. "You're painting the last bathroom, and there is no way you'll want to do it after that. Plus, it'll feel good. And maybe," here's the kicker "you could have a little bit of bread"

The first advantage to having PCOS-insulin resistance that I have found. I get to see *immediate* results from aerobic exercise. Exercise temporarily increasing your insulin sensitivity, and the effect, at least in early studies in non-obese subjects, is roughly quadrupled if you are on what researchers call a 'carbohydrate deprived diet' (aka, low carb). Not only does the sensitivity increase, but the length of time the effect lasts increases. Not too shabby. Early data for me would seem to suggest that even the relatively puny amount of aerobic exercise I'm doing now increasing my sensitivity enough that I can add one small, low glycemic load carb back on the day I run. I'm talking a toddler sized portion of something like beans or barley. But you know what? I'll take it. I'm trying not to get my hopes up, but wouldn't it be nice if it meant I could indulge every now and then?

Anyway, I put on my running skirt and my running shoes, grabbed Penny's leash and we were off. I waited until the sun was dipping below most of the tree tops, so we could at least run in the shade. I was expecting my legs to burn. For every inch to be a struggle.

But it shockingly wasn't. I wasn't quite as smooth as I was Monday, and it was hard on the last push, but it was actually enjoyable. I didn't have to think so hard about breathing or how to do it. Penny has started to figure out that 'jog' means 'walk twice as fast, don't bolt', and to go in a straight line, not try to circle back to me. So I didn't have to worry about tripping over her, and she didn't get stepped on. And now I am writing this blog post and she is enjoying lying in the grass outside. I think jogging will work out well for the both of us.

Jogging, Day 2

After taking yesterday off jogging (but walking my usual 5 miles), I found myself looking forward to it today. What is this? I don't look forward to exercise. Its the thing I do because I have to, or because I want to be in good shape for something. I got in shape before my wedding so I could enjoy hiking with my newly minted husband. I started walking 5 miles a day so I could eat a few carbs a day. The only exercise I do to enjoy it is yoga. Initially I blamed it on the caffeine from a Starbuck's coffee I indulged in (sugar-free hazelnut syrup...mmm), but I don't think that was it. Weird. 

Anyway, jogging today was a little harder than on Monday. For one, it was about 10 degrees hotter. A cat crossed our path and completely distracted Penny. By which I mean she thought that since we were already running, we could chase the cat. So we had to go through the stop, sit, wait, ok, pull, stop, sit, wait routine for about 5 minutes until the cat was well gone, and Penny had forgotten about it. Oh well, lesson in leash manners. I shortened my intervals to run four houses, walk four houses, mostly because of the heat. I wanted both of us to last the two miles. 

And we did. And I felt pretty good afterward, though feeling it in my thighs. I realized however that I have terrible running form. I'm going to need to work on that. Maybe ask some friends who run for advice.  Penny is not nearly as tired as she was Monday, but she adapts quickly. She is going to be a big motivator in keeping going, both because it is fun to run with her and because it is nice to have her sleep or play quietly, and not try to jump on my desk.

Now let's see what happens on Friday. Learning to jog, one day at a time.

"Just as I am, without one plea": A meditation

Have you ever had the feeling that you need a word, a song, a something, but can't quite put your mental finger on what you are looking for? I've been having that feeling for the past week or so. There was a hymn somewhere in the back of my mind, I knew it was there, but I couldn't for the life of me remember what it was enough to sing it or even look it up. I have felt a calmness the past couple of days, and I know this was somehow a part of it, but I just couldn't dreg it up out of my subconscious. Hymnary is an amazing and indispensable tool for many things, but it is especially good for when I know I want a hymn, but have only an inkling of what I want. (It is also the only tool I know of where you can search by melody fragment). 

All of that is by way of saying "Just as I am, without one plea" is what has been flitting on the edge of my mind recently. It is one of those songs I have a very hard time singing without crying, but fortunately that is not an impedance to writing about it. If there were a dictionary of descriptive terms, under 'simple and plaintive' would be this hymn. Written by Charlotte Elliot around 1833, it was written as a mediation on how she came to Christ and as a statement of faith. It was first published in The Invalid's Hymnbook (Elliot was herself semi-invalid after a severe illness when she was 32), and according to Hymnary's count has been included in 1,408 hymnals to date. In four short stanzas of 4 verses each*, she lays out every Christian's walk of faith.

Just as I am, without one plea,
but that thy blood was shed for me,
and that thou bidd'st me come to thee,
O Lamb of God, I come, I come.

Just as I am, and waiting not
to rid my soul of one dark blot,
to thee, whose blood can cleanse each spot,
O Lamb of God, I come, I come.

Just as I am, though tossed about
with many a conflict, many a doubt,
fightings and fears within, without,
O Lamb of God, I come, I come.

Just as I am, thou wilt receive,
wilt welcome, pardon, cleanse, relieve;
because thy promise I believe,
O Lamb of God, I come, I come. 

The first stanza reminds us of something we often forget--we have absolutely no claim on God except through the blood of Christ. "Good people don't go to heaven. Forgiven sinners do" is the short reminder I sometimes see on cars around here. "For by grace you have been saved through faith, and this is not your own doing; it is the gift of God— not the result of works, so that no one may boast." (Ephesians 2:8-9). There is nothing we bring to the table, except the name of Jesus. But Elliot also reminds us that Christ has not only washed us in His blood, but "bidd'st [us] come". He invites the little children to come to him, and tells his disciples that the kingdom of heaven belongs to such as them (Matthew 19:14). Over and over, Christ invites people, bids them come to him. Our God is a welcoming God. All we have to do is 'come'. 

The second stanza places special emphasis on the cleansing power of Christ's blood. It is one of those images that is somewhat paradoxical. Normally, we think of blood as staining. Its right up there with wine and ketchup on those commercials touting the cleaning power of a detergent. We think of it staining the hands of a murder. Think of the scene in Macbeth where we witness Lady Macbeth's sleepwalking, wringing her hands and trying to wash out the blood. And yet as Christians we constantly use this image of being washed white in  the blood of the Lamb. It is of course a metaphor, but its still a little strange. And yet here, Elliot doesn't dance with the metaphor. Doesn't play theological tricks with it. Its simple. Our souls are covered with dark blots, like a shirt who had a pen burst in the pocket. But no elaborate ritual, no multistep process with three different chemicals are needed to remove these stains. Though the dark spots on our souls are literally 'damned spots', accepting a washing in Christ's atoning blood is all that is needed, and is freely offered, if we would but come.

The third stanza deals with that topic that every Christian deals with, and few like to talk about, except in the context of "I'm not like that anymore". The fact that often we still feel conflicted, doubtful, fearful. We are freed from the power of sin and death, not from fallen human condition in this life. How often was Peter, on whom Christ laid the church, fearful? Conflicted? He doubted Jesus as he was walking on the water to him. We can't possibly expect to do better. The good news is Christ doesn't ask us to come after we're sure. After we've weighed the pros and cons and come to a decision. He does not ask us to come to him after we've gotten over our fears. He will take us just as we are, flaws, sins, doubts, fears and failings all, if only we will come to him.

And here, in the fourth stanza, is our declaration, our hope and our joy. Christ will take us just as we are, with all our brokenness, our guilt, our fear that we don't belong, and takes it all away. We are welcomed as honored guests, our sins are removed as far from the east is from the west, their stains are forever removed, and all our fear, our pain, our brokenness healed. If only we will believe in his promises, by grace through faith, and come unto Him.

*Thanks Dad, for correcting my terminology.