Saturday, June 8, 2019

Math Tricks

How do we make sure our students are making the connections between concepts that are necessary for them to have good number sense and a solid understanding of the math they are doing?

My first year teaching I was worried that what I was teaching might go over my students' heads. The way I dealt with this was to use tricks and stories to help them understand things like solving one-step equations or dividing by fractions. I had learned some math concepts this way as a student, so I thought it made sense to teach it to my students. This made me feel like I was continuing in the grand tradition of math teachers, so I didn't really stop to examine what I was doing or why. It's just how it had been done. What I found was these tricks not only muddied the waters while they were learning with me, but very few of those tricks held up past my class. 

"When we ask children to follow a procedure that holds no meaning for them, they will conclude that math does not make sense. Go back to the mantra “math makes sense” and make sure all students believe it..." - Tina Cardone, "Nix the Tricks"

I was not setting them up for success down the road by telling them to "keep, flip, change" when dividing by fractions. I was also discounting my students' ability to understand what was really happening within math; I was insulting their intelligence and dumbing things down.

Let's examine putting the bigger number on top when subtracting as a simple example of why tricks are dangerous. Many of my students would recoil in horror if I put a problem on the board like 7 - 10. "You can't do that!" they would shriek at me, worried that the time/space continuum was about to collapse before their very eyes. At first, I couldn't understand their revulsion, until they explained to me that you must put the bigger number on top when you subtract. Since most state curriculums do not introduce negative numbers until 6th grade, I understand what their elementary teachers were trying to accomplish by teaching them this "rule." In all their experience, my students had started with a number and taken an equal or smaller number away from it. This "rule" worked for every situation they had encountered prior to meeting me. 

A more concrete way to teach subtraction is to give students manipulatives such as ten frames or unit cubes or base ten blocks. This way, they can start with one amount and take some amount away. If they need to regroup, they can break apart a ten or a hundred physically. Another method is to have students model subtraction on a number line. This method also allows students to explore negative numbers more easily and naturally. Once students understand what is going on when they subtract, moving to the standard algorithm becomes easier and makes more sense.

I came across Nix theTricks as a second year teacher, which helped me explore different methods for teaching math which were simpler and more straightforward. I have tried over the years to break my own bad habits of teaching math concepts in unnecessarily complicated ways, and each time I am successful, my students benefit greatly. Not only does it save time during the initial lessons, but when we need to use previously learned math in order to problem solve and learn something new, my students have a firmer foundation and a better understanding that allows them to make new connections.

What are some tricks you have stopped using in your lessons? Share in the comments!

Monday, June 20, 2016

Number Talk Discussion #10

186 ÷ 6

There are a number of ways to approach this problem. Before we look at them, let's define each term of the division problem. 
186 is the dividend, or the number to be divided by another number.
6 is the divisor, or the number you divide by.
The answer to the problem (31 in our case) is called the quotient.


Multiply Instead
"I know 6 times 30 is 180, plus one more 6 gives me 186; so my answer is 31."

Expanded Form (Chunk it Out)

Make a Tower

Halving and Halving

Which of these methods work better for this problem than others? Did you try any methods not listed here? Share in the comments below!

Friday, June 17, 2016

Monday, June 13, 2016

Number Talk Discussion #9

146 + 197

Round and Adjust

Take and Give

Start from the Left

Break one Addend Apart

Add Up


Did you try a different method? Are some methods more efficient for this problem than others? Share in the comments below!

Friday, June 10, 2016

Monday, May 30, 2016

Number Talk Discussion #8

43 + 9

There are a number of ways to approach this problem. Before we look at them, let's define each term of the addition problem. 
43 and 9 are both called addends.
The answer to the problem (52 in our case) is called the sum.

Round and Adjust

Take and Give

Start From the Left

Break One Addend Apart

Add Up

Did you try a different method? Are some methods more efficient for this problem than others? Share in the comments below!

Friday, May 27, 2016