This week one of the math skills our cooperating teachers was having the students work on is the concept of one more and one less. Almost all of our students are able to answer quickly and correctly when asked questions such as, “What is one more than 5?” or “What is two less than 8?” Since this concept was proving to be simple for the majority of our group of students, we decided to make the more or less questions a bit harder. However, what we thought was a little harder was actually very difficult for the students to comprehend. Using marbles as manipulatives, we asked the students, “How many more marbles do you have than me?” I had set two piles, one for the student and one for myself on the table. The student would look at the piles, count each and then state the amount of marbles that were in the largest pile. The students had troubles grasping the concept of “How many more”.
I then demonstrated how one could go about finding the answer by lining one pile of marbles in a straight line, and then lining up the other pile of marbles next to the first line. Therefore, the student would be making groups of two, one marble from the first pile and one marble from the second. Once the student had lined the piles up next to each other, one of the lines would be longer than the other, because the two piles are not even. The marbles that were not matched in a pair, I labeled as the ‘extras’. I explained that by counting these extras, one could tell how many more one pile had than the other. The student understood, by verbally stating, that a pile that had 3 extra marbles, had three more marbles than the other pile.
Once I demonstrated multiple instances of “How many more” problems, stating and explaining exactly the same way as I first had, the students were unable to complete a problem on their own. Even if I gave them a hint to line up the marbles as we had together, the student was determined to count the total amount of marbles in the largest pile and state that that was how much ‘more’ that pile had than the other. I could not seem to convince them to use the exact demonstration I had used the first time. Next week I want to try to use white boards to demonstrate the “How many more” concept. I will have the students cross out one object from one pile and then one object from another pile until we have crossed out all of the marbles in one of the piles. I hope this will stop them from recounting each object in the largest pile as a first instinct in answering “How many more” there are.
Posted on January 21st, 2013 by stephanielorr10
Filed under: Uncategorized