Tuesday, March 20, 2012

Rate of change of beaker.

Here is a lesson you can do with your students on related rates of change:

Before this, ensure your students understand at least similar triangles and have seen some related rates questions before.

1) Bring students to a chemistry lab with different beakers, or bring different beakers into your class.  **You will need a water tap**

2) Divide the students into groups of 3 or 4 and provide each group with one of each of the following beakers, shown in the picture below.

 3) Provide the following question to the students:

 Hypothesis:  Will the height change at a constant rate or will it change throughout, if we were fill these beakers up with water? Explain.  If the rate of change of the height of the water changes, when will the rate be the largest, and when will it be lowest.

Procedure: Turn the tap on and record the time it takes to fill the beaker up to the last marking on the glass, using a constant stream of water.  Record this three times and average your times.  What does this represent?

Fill up both beakers, using this stream of water.  Was your hypotheis correct?  If not, what did you notice?

Calculations:  If you were to fill up the cylindrical beaker with the stream of water how fast would the height change when it was half full? When it was entirely full?

If you were to fill up the conical beaker with the stream of water how fast would the height change when it was half full?  When it was entirely full?

I have used this before with my students and watched how they had to determine not only WHAT to measure but HOW to measure it.  Feel free to use, change, tweak as you see fit.

Here is video one student made:


And his Prezi:

Monday, March 19, 2012

The problems of Merit Pay

The problems of Merit Pay:

If you have been following any of the Wild Rose Alliance Educational polices in Alberta, you will find that they are a supporter of Merit Pay in Education.

What is Merit Pay?
Teachers, and others in education, will be paid based on the results their students attain on standardized exams. At first glance, this sounds great. If a business is rewarded, with more profit, as their sales increase, why shouldn’t teachers get paid more if their results increase?

The problem…
Without getting into truth behind standardized exams, I am going to address the real issues, but first let’s take a look into history..

We start in 1887 in Denver Colorado where the government tested students to determine how much a teacher was worth. David Berliner and Sharon Nichols’ wrote about this experience in Collateral Damage, here is an excerpt:

Another warning about the dangerous side effects of high-stakes testing surfaced, when a plan to pay teachers on the basis of their students' scores was offered, making student test scores very high stakes for teachers. A schoolmaster noted that under these conditions, "a teacher knows that his whole professional status depends on the results he produces and he is really turned into a machine for producing these results; that is, I think unaccompanied by any substantial gain to the whole cause of education."

We then travel to mid 19th-Century England, where a “payment by results” plan was implemented into the Education act. Wade Nelson, a professor at Winona State University, summarized the evaluation saying “Schools became impoverished learning environments in which nearly total emphasis on performance on the examination left little opportunity of learning”.

In The Public Interest, a right-wing policy journal, two researchers concluded with apparent disappointment in 1985 that no evidence supported the idea that merit pay "had an appreciable or consistent positive effect on teachers' classroom work." Moreover, they reported that few administrators expected such an effect "even though they had the strongest reason to make such claims."

Educational historians David Tyack and Larry Cuban have clearly stated that "The history of performance-based salary plans has been a merry-go-round. In the main, districts that initially embraced merit pay dropped it after a brief trial." But even "repeated experiences" of failure haven't prevented officials "from proposing merit pay again and again."

Lastly, the Alberta Teachers Association opposes Merit pay on the following grounds:
• no agreement exists on what constitutes “good” teaching;
• no reliable measure of teacher efficiency exists;
• merit pay undermines teacher morale;
• merit pay is not a quick-fix scheme for any ills that might affect a particular jurisdiction;
• it doesn’t save money;
• it is not a “magic bullet” for increasing student performance; and
• individual merit pay works for few organizations today because most emphasize teamwork and collegiality.

If we start basing salaries on the results of achievement in schools, then achievement, not learning, will be the focus.

Wednesday, March 7, 2012

The power of Twitter

Recently, a student of mine needed some help. Instead of giving up, she picked up her phone, logged onto Twitter, and her and I had the following conversation:

She was able to explain her thought process in under 144 characters. What happened next, made me smile even more!! I asked her if she understood the first concept of the class, when she expressed that she has not had a chance to look at it yet, something amazing occurred. Check below:

Liam, graduated from Notre Dame last year, and because of the power of the virtual world, is able to assist students who are now enrolled in the course he excelled at!!
Lastly, Twitter is free and the possibilities are limitless!