|Practicing subtracting with regrouping|
Grabbing my bins of base ten blocks, I sat down and started using them to instruct and SHOW the meaning of subtraction. Reviewing the idea of "trading" the tens for ones and hundreds for tens was the first step. I then gave the students a number to 'build' with the base ten models. From there we came up with a number to subtract. I modeled how we would use the blocks. It was then the students turn to use the blocks to subtract (they were NOT writing yet, but I was recording each step on a white board for them to see.) In this way, we continued through many, many problems until the kids were comfortable with the idea of subtracting and regrouping with just the manipulatives.
Eventually, I heard the words I had hoped would come,"OHhhh, I GET IT!" The math tools had worked - they students were able to make that connection between the concrete and abstract! The students were now ready to move onto the next step of using the manipulatives and recording the steps on their own to just using the algorithm.
Base Ten Blocks, Pattern Blocks, Money, and Square Tiles are just some of the math manipulatives that are helpful to use in classrooms to help children explore the sometimes abstract world of math.
For teachers who don't have these types of tools available there are many Virtual Manipulatives available on line. The following are some of those sites that help bring abstract concepts come to life.
NLVM: National Library of Virtual Manipulatives. Manipulatives for use with PreK - Grade 12 students in the areas of Numbers and Operations, Algebra, Geometry, Measurement & Data Analysis.
Math Playground: Contains manipulatives for fractions, Algebra, angles, percents and more.
Teacher LED: A site to use with an Interactive Whiteboard to help with mathematical understanding. (not just virtual manipulatives)
Shodor Interactivate: A site with lessons, manipulatives and activities.
How to Make the Most of Math Manipulatives: An article in Scholastic by reknowned Math Educator, Marilyn Burns with other helpful links.
Manipulating Math: Concrete Vs. Abstract: Blog post in Teach Hub by the author of Thinking Outside the Box Blog
The Use of Manipulatives in Math Instruction: An article in LDOnline by Louise Spear Swerling which discusses the pros and cons of using these tools.
Learning Mathematics with Virtual Manipulatives: by CITEd (Center for Implementing Technology in Education) includes an article and resources.
|Subtraction with NLVM site|
(Managing these tools can be challenging and I find that sometimes I do not use these tools because they can be cumbersome and difficult to distribute. I welcome your ideas on best practices with the storage and distribution. Feel free to leave your ideas in the comment section below. Also, please let me know of your success or concerns with using different math tools.