Monday, November 23, 2009

Salt Crystal Lab

In the salt crystal lab, the students are growing crystals from three types of salt: iodized table salt, un-iodized table salt, and Epsom salt. Each group prepared a saturated salt solution, added food color, and then poured each solution into each half of a Petri dish (one half contained a sponge and the other was empty). See pictures from one group from each class.





For this lab, I gave an overview of the procedure while the students were at their desks. I also had them answer three questions before the could get the boiling water that they needed to make the salt solutions. My goal was to get them to listen, read, and pay attention. I think the lab went well, but it's difficult to get everyone to listen to and/or read the instructions before they start the lab. Hopefully everyone will have salt crystals next Monday.

Wednesday, November 18, 2009

Slime Lab

The planning and execution of my first chemistry lab was an experience. The planning went well, I had enough supplies for both classes, but I didn't factor in that some of the students would make mistakes and have to start over.

For this lab, the students were organized into eight groups of four. Each group had to make four types of slime: floam, silly putty #1, silly putty #2, and slime; each student in the group made one type of slime.

Overall, the students were excited to do the lab and they had fun making something that they could take with them. They students were able to take their slime home in a resealable sandwich bag. Quite a few of them didn't follow the instructions, so their slime, floam, or silly putty didn't come out right.

I think next time, I'll go over the procedure before I send them back to their lab stations.

Thursday, November 12, 2009

Planning a slime experiment

The students have finished a section on the periodic table and are moving into chemical and physical changes. Next week I am planning a slime lab, where the students will be divided into eight lab groups and each person in the group will make a different type of slime. Differences in the properties of the slime are determined by the added materials beyond the basic materials of borax and white glue solutions. Slime variations are created by adding polystyrene beads, cornstarch, soluble fiber (such as metamucil) or cornstarch and vegetable oil.

Wednesday, October 28, 2009

Chemistry in everyday life

On Monday, October 26, I asked several students in 2nd and 3rd hour to write down, on a notecard, three things that they think of when they hear chemistry. The most common responses were chemicals and labs or experiements. I was hoping for responses like materials (e.g. plastics, synthetic fabrics) or food, things that the students encounter on a daily basis.

Now that the students have begun covering chemistry basics, my plan is to focus presentations on the chemistry that they encounter in their everyday life. I gave my first of such presentations today on water treatment (which is part of the field of environmental engineering). I made some connections to myself and what I do as an environmental engineering and emphasized why water treatment is important to their lives; I think the students got the point that I was trying to make. No one thinks about water treatment, they just expect that the water from the faucet will be safe to drink, and by safe I mean won't make them sick. Most people doesn't know what happens to things that go down the drain.

Monday, October 19, 2009

Attention

Some of the students who are struggling with the material and seem to only work when they receive individual attention. For journal questions and worksheets, if I see that a student has paper and pencil in front of them but aren't working, I'll ask them if they understand how to do the work. Usually they don't so I'll take the time to explain and walk them through the problem(s). For worksheets I'll stay with the student long enough to make sure that they can do the work on their own, then I'll move on to someone else and I'll return to make sure that they continue working on the assignment.

Both physical science classes, second and third hours, have spent the first month and a half of the school year going through the basics, such as lab safety, the scientific method, units, and measurements; all of which are important, but I don't think Ms. P wanted to spend that much time on this material. It is clear that some of the students are struggling with the material and others get it right away. How do you find the right pace?

Second hour is a difficult class to work with. There are 35 students in the class, which is too many, and a few of them are very disruptive and disrespectful. On the other hand, there are students in the class who come to learn, and several of the students should not be in physical science; they should be in physics or chemistry. Third hour is easier to work with; it's a smaller class, and the combination of personalities is much calmer. The students in third hour stay focused longer and they get more work done in class.

Wednesday, September 30, 2009

Measurements

Today I gave my first presentation. The topic was "Why measurements are important." The students are currently reviewing SI units and several of their lab activities involve measuring various things. With the ~10 minute presentation I wanted to bring in a real world connection, since it's not obvious how important accurate and precise measurements are to everyday life.

The format for this presentation was different from the ones I gave last year. The presentation was designed to be short (10-15 minutes) and I wanted it to be a question oriented discussion (read that as more interactive) rather than me just talking at them.

Sunday, September 20, 2009

Back for a second year

I'm back in the classroom for a second year in the K-12 Partnership Program. This year I'll be in two physical science classrooms; it is my understanding that physical science breaks down to a semester of intro chemistry and a semester of intro physics. Most of the students are 10th graders and there are a few 11th graders.

My first day in class I introduced myself by telling the students a little about my educational background, how I came to be in their class, my goals, and a personal note (hobbies and favorite sports teams). I saw some students from last year, and I greeted them once the activity for the day began.

For the first few classes I want to become familiar with how the class is run. The students had a review of lab safety and are currently working on the scientific method.