Categories
Doesn't really fit anywhere

“18 is a power of 3.”

“18 is the power of 3 after 9.”

 

I made this mistake in my own math work several times today in the midst on working on some other problems. I’m happy to answer any questions anyone has about my thought process in the comments.

 

 

Categories
Doesn't really fit anywhere

Dividing

What’s the mistake? Can you figure out how this happened?

If we’re nice then maybe Nico Rowinsky¬†will slip into the comments and let us know what happened with this kid.

Categories
Doesn't really fit anywhere Numbers & Operations in Base 10

Division by Zero

5 divided by 0 is 0.

Thoughts?

Related: http://rationalexpressions.blogspot.com/2012/11/how-not-to-teach-it-division-by-zero.html

Categories
Doesn't really fit anywhere Number & Operations -- Fractions

Whole numbers and 1

This one is really interesting. We’ve got both a sample of student work, and on the left the student has crossed out \frac{5}{1}. We also have a record of the following student question:

Kid: [Raises hand.]

Teacher: “What’s up?”

Kid: “Are you looking for a 1 or, like, the number 1?”

What is the student’s question, and what does it reflect about what he knows and thinks? How would you help?

[The submission also comes with an answer, yielded by the teacher through further questioning, revealed in the comments.]