This is my first attempt to use Desmos, the outstanding free online graphing calculator (and a free iPad app). I'm sure many of you have been utilizing this powerful resource. There are already many available teacher samples you can use.
CLICK ON THE GRAPH TO LOAD THE APP.
Let me know if you can view the graph (you may have to adjust the window slightly). More importantly, what do you think of the activity and do you see its potential for deepening understanding of algebra?
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Sunday, April 20, 2014
Posted by Dave Marain at 7:29 AM
Tuesday, April 15, 2014
While I agree with the concerns of many parents that over-testing is damaging to children and subverts the purpose of education, I don't believe that the Common Core has set the bar too high, at least in math, my area of expertise. I know from direct experience with children that we can expect far more thinking of them than is commonly held. That is the Core Belief of my blog.
The problem is that teachers have not received the necessary preparation and the testing has been rushed and lacking in quality control.
We're trying to set the bar higher for children without raising the bar for those responsible for implementing these changes. That is irresponsible at best and criminal at worst.
Posted by Dave Marain at 8:31 AM
Saturday, April 5, 2014
Posted by Dave Marain at 3:01 PM
Sunday, March 30, 2014
The MathCast below is a more sophisticated % problem which requires processing several pieces of data expressed in percent form. Students have to make sense of the information and develop a model to represent the data. Both a tree model and a table/spreadsheet approach are demonstrated.
These are the kinds of data-based applications which will become a central theme of the newer assessments from PARCC, SBAC and the College Board.
Sorry, you'll have to watch the video to see the problem but I'll give you a glimpse:
70% of the left-handed students surveyed were boys...
Watch "SAT/Common Core Data-based Percent Challenge" on YouTube - SAT/Common Core Data-based Percent Challenge: http://youtu.be/mhQN8imj-Pg
Also, pls let me know if these MathCasts are blurry.
Posted by Dave Marain at 6:07 PM
Monday, March 24, 2014
David Coleman of the College Board has stated that ratios, percents, etc., will be an important focus of the new SAT, particularly in an applied setting.The MathCast below demonstrates a classic medium-hard percent word problem which should continue on all of our "new" assessments.
Watch "40% of the 9th grade... Percents,New SAT and…" on YouTube-40% of the 9th grade... Percents, the New SAT and…: http://youtu.be/WjNQ8VHhD4U
I encourage all my readers to offer constructive criticism re both the content and the technology of these videos and suggest topics/problems for future MathCasts.
Posted by Dave Marain at 8:07 AM
Wednesday, March 19, 2014
A hard adjustment for parents/educators who were raised as I was on traditional algorithms. Of course, understanding the rule for multiplying fractions DOES NOT mean students should use this to get the result.
Teaching conceptually is fundamental to the Mathematical Practice Standards of the Common Core. BUT this should be BALANCED with traditional methods. Current thinking is that the way we learned may be far more efficient but it leads one to think of math as just a set of meaningless rules. Kind of like a "black box." I see the need for both.
After watching this MathCast you'll probably conclude this is way too confusing for students not to mention adults! Just remember, some of that confusion results from sloppy drawings and carelessly worded explanations. I'm definitely guilty of both!
Watch "SHOWING one-third of three-fourths vs Traditional" on YouTube - https://www.youtube.com/watch?v=8vtce4rz9dE&feature=youtube_gdata_player
Posted by Dave Marain at 8:18 AM
Sunday, March 16, 2014
These types of more challenging exponent problems requiring strong manipulative skills will probably not go away on the New SAT!
And on the NON-CALCULATOR section!
You have to watch the video to see the solution!
Watch "5^(2x)=4; Non-calculator exponent SAT-Type Problem" on YouTube - 5^(2x)=4; Non-calculator SAT-Type Problem: http://youtu.be/yaxx31L75hM
Posted by Dave Marain at 2:38 PM
Saturday, March 8, 2014
A classic SAT math challenge that will probably not go away on the new SAT coming in 2016. And just imagine if calculators are not allowed for this!
Watch "4% of 8% of 16x is what % of 2x? New SAT, Common Core and Percents Pt 1" on YouTube - https://www.youtube.com/watch?v=WY58ebnZvCI&feature=youtube_gdata_player
Posted by Dave Marain at 12:37 PM