Hi Monica! No, not at all! Using mental math strategies actually improve understanding because students better understand what the numbers really mean. In subtraction, there is a similar strategy called Expanding the Subtrahend. You can see my You Tube video about it here: http://www.youtube.com/watch?v=tI5AXWGqb_w
I have aced Calculus and Matrix Transformations in college, and been a computer programmer for 30 years, and I feel DUMBER after reading these ridiculous techniques.
If you feel dumber after reading these "ridiculous techniques," you obviously have never taught math to a diverse group of young learners. Congratulations for acing Calculus and Matrix Transformations and for being a computer programmer for 30 years. You are in an infinitesimal percent the world's population. While you are very lucky that math skills come easily to you, they certainly do not for everyone. Most children that I work with need strategies to be explicitly taught to them in order for them to be successful in math. You should be ashamed of yourself for insulting someone who dedicates so much of her free time (and own money, I am sure) providing resources to help CHILDREN.
Thank you for your time and for sharing your techniques. I have been looking for a way that I could use to back up my boys and girls learning from school while using my understanding of maths. What you have provided here works well for me.
we certainly teach this strategy for all 4 operations but we call it the partial products or splitting method. It is a fantastic way for students to break numbers into smaller (or easier) parts mentally and then perform the operation. Love it!
The ancient Greeks used not only front end addition, but front end multiplication. Examples are given in “A Manual of Greek Mathematics” by Sir Thomas L. Heath (Oxford University Press, 1931, still in print from Dover Publications), p. 29-32. I ran into a method of doing front end arithmetic for the first time many years ago in middle school, in the early 1960s, reading the regular math article in “Science and Math Weekly” (SMW) which I got at school while other kids were reading My Weekly Reader, Junior Scholastic, etc. Heath’s book gives some examples from Eutocius’ commentary on Archimedes. The SMW article noted our common method of long division is already front end arithmetic, and Heath gives an example of division from Theon of Alexandria, and even gets into extraction of numerical square root. Yes, students SHOULD reach for their calculators on tests, because the objective is to get a correct answer, and get it quickly; but they should all know HOW to do these operations by hand, or mentally – better to understand what they are doing.
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Thanks so much for your post. You answered some questions that I had been searching the web for. 🙂
Do you find that this strategy confuses students as they begin to subtract?
Hi Monica! No, not at all! Using mental math strategies actually improve understanding because students better understand what the numbers really mean. In subtraction, there is a similar strategy called Expanding the Subtrahend. You can see my You Tube video about it here: http://www.youtube.com/watch?v=tI5AXWGqb_w
Have a great evening,
Shelley
I have aced Calculus and Matrix Transformations in college, and been a computer programmer for 30 years, and I feel DUMBER after reading these ridiculous techniques.
If you feel dumber after reading these "ridiculous techniques," you obviously have never taught math to a diverse group of young learners. Congratulations for acing Calculus and Matrix Transformations and for being a computer programmer for 30 years. You are in an infinitesimal percent the world's population. While you are very lucky that math skills come easily to you, they certainly do not for everyone. Most children that I work with need strategies to be explicitly taught to them in order for them to be successful in math. You should be ashamed of yourself for insulting someone who dedicates so much of her free time (and own money, I am sure) providing resources to help CHILDREN.
Thank you for your time and for sharing your techniques. I have been looking for a way that I could use to back up my boys and girls learning from school while using my understanding of maths. What you have provided here works well for me.
we certainly teach this strategy for all 4 operations but we call it the partial products or splitting method. It is a fantastic way for students to break numbers into smaller (or easier) parts mentally and then perform the operation. Love it!
The ancient Greeks used not only front end addition, but front end multiplication. Examples are given in “A Manual of Greek Mathematics” by Sir Thomas L. Heath (Oxford University Press, 1931, still in print from Dover Publications), p. 29-32. I ran into a method of doing front end arithmetic for the first time many years ago in middle school, in the early 1960s, reading the regular math article in “Science and Math Weekly” (SMW) which I got at school while other kids were reading My Weekly Reader, Junior Scholastic, etc. Heath’s book gives some examples from Eutocius’ commentary on Archimedes. The SMW article noted our common method of long division is already front end arithmetic, and Heath gives an example of division from Theon of Alexandria, and even gets into extraction of numerical square root. Yes, students SHOULD reach for their calculators on tests, because the objective is to get a correct answer, and get it quickly; but they should all know HOW to do these operations by hand, or mentally – better to understand what they are doing.
Love your posts! Have a lot of ‘a-ha!’ moments after reading them! Thanks for creating them and sharing them 😁👍