Showing posts with label open questions. Show all posts
Showing posts with label open questions. Show all posts

Thursday, November 17, 2011

Open Question Attempt #2

This was the open question I posed to my Advanced Algebra 2 students today:

Write a system of inequalities that has (4, 3) as a part of its solution. It should have 2 or 3 inequalities. (I had thought about leaving the last sentence off, but I was trying not to overwhelm them.)

When I asked for their answers, I got crickets again. (Recall, I had tried this with them a couple of weeks ago and pretty much got no response from them.) So, I asked them for one inequality that would work. Crickets. More crickets. That, and a "I don't know how to work backward." After a few moments, someone gave me one inequality. So we graphed it and checked (4, 3) and it didn't work - (4, 3) was on the line. I asked him how to change it and he thought about it and came back with a different inequality. This time (4, 3) wasn't on the line, but he had the wrong inequality symbol. We flipped the inequality and had a working inequality. Yay! How about a second one? Crickets.... but for a shorter time. Same student, new inequality. Worked - success!

Can we come up with 2 different ones? Just try... Different student, new inequality. Got a working one and the student came up with a second one.

By the time we were done, we came up with 5 systems (look at the first 3 pages of the pdf below - first 5 slides). The first time we did an open question, I primarily had 3 students contributing. This time I had 6 or so contributing - 4 of them who had not last time. I'll take the improvement. Maybe next time, I'll have more.




Tomorrow I'm trying this question with Algebra 2 (similar to what I did with my Advanced Algebra 2's a couple of weeks ago):
I know that (2, 3) is the solution to a system of equations. Find two equations (in x and y) that have (2, 3) as their solution. How do you know that (2, 3) is the solution?
(I think that's how I phrased it.

Wednesday, November 02, 2011

An attempt at an open question

I gave my Advanced Algebra 2 students the following question today to open class:

Write a system of equations with two equations and two variables with a solution of (2,3). Be prepared to justify your answer in two ways.

We have done solving systems of equations by graphing and substitution. We started elimination yesterday. I had hoped that they would come up with equations by working backwards - for example, 2 + 3 = 5, so x + y = 5 is one equation they could use in the system. I had hoped that once they got the equations, they would use either substitution or elimination to check the solution was (2,3).

What I got was blank stares. They had no idea where to start. I ask them to give me one equation and we'll put together a system. Then the student I have from the ED (emotionally disturbed) unit - who is bright mathematically - raises his hand and gives me an equation. Then he gives me a second one. And, right or wrong, I take the time to show them that (2,3) is a solution to it, first by substituting the values in to check and secondly by using substitution since it made the most sense for the equations he had given me.

I asked them to give me two more equations, and after a few moments, I had two more equations, one each from two different students. Demonstrated that (2,3) was the solution again. I asked them for two more equations and got two more equations, this time a little quicker from my students.

After I was done checking the third system of equations, I did talk with them a little about how I wanted them to understand what the solution to the system meant.

I'm still behind on More Good Questions and I guess I need to read some more to have a better idea of how to handle open questions with my classes. I decided to try this with my Advanced Algebra 2 class since they are a little more willing to think and work at stuff than my regular kids. I'm not totally sure what I wanted to get out this, but I had hoped for better responses from them. Will have to read more and think more before bringing in the next open question.