Learning about Integers and a Problem Solving Strategy

Today in class we learned about what an integer is and then practiced using integers in a variety of questions. Below is the lesson we did in class.

Students were very good at thinking of situations in which integers would be used and identifying the appropriate integer given a statement (eg. I spent $15 might be -$15). They had much more difficulty solving word problems which involve the use of integers. When solving word problems, often the hardest part is identifying what the question is asking them to do. Often students get bogged down by the volume of information and then have difficulty identifying what the actually need to do.

To assist with this, I encouraged students to write down all the information that the problem gives them, and then write down what the question is asking them to do. I told them this is usually at the end of the problem. Often, once students have all of the information written down, they already have a strategy to solve it, so I ask them to write this down as well, and then try it out. Later we will learn how to look back to prove their thinking. How can you tell me it is the right answer? How can you prove it to me?

Here is an example:

"A ski lift at a ski hill starts at 800m about sea level and ends at 1400m about sea level. For each 100m rise in sea level, the temperature goes down by 2ºC. If the temperature at the bottom of the hill is 3ºC, what is the temperature at the top?"

Here is how I would solve this:

Know:
- ski hill starts at 800 m
- top is 1400m
- for each 100m up the temperature goes down 2 degrees
- temperature at the bottom is 3 degrees
- I HAVE TO FIND - the temperature at the top

Plan - draw a picture? Make a table? Use a number sentence? I think I will use a t-table to help me.

In my table I decided to go up by 100's because in the problem it said the temperature drops for every 100m. In the table, I can see that the temperature is going to be -9 degrees at the top of the hill.

Please take a look at the integers slideshow to see exactly what we did in class today. If you have any questions, please feel free to contact me at school any time.

Integers