Categories
Addition Number & Operations in Base 10

8 + 32 = 40 <--- wait, what's the mistake??

Greetings from Singapore!

This is from my son’s Primary 1 workbook. He had written 38 instead of 32 in the top row and 2 instead of 8 in the second row.

The submitter thinks that this teacher’s feedback was probably not so effective, and I’m inclined (from a distance, obviously) to agree:

The teacher’s marking indicates that my son should fix his mistake in the parentheses provided. Yet seeing the “mistake” made me pause. I suppose that if the focus is on simply getting the numbers transferred correctly, then it’s a mistake. Yet if the focus is on finding the sum, and stating the relationship between the two numbers, then perhaps it shouldn’t be considered a mistake. This is interesting to me not so much because it reveals what’s going on in the kid’s head as it does how often teachers have narrow ideas of what’s correct. As for what’s going on in the kid’s head, he could’ve simply been rushing. He correctly transferred the numbers in the other problems on the worksheet. This “mistake” could’ve been used to spark a discussion about why the correct answer was obtained and when it’s appropriate to shift quantities around and when it isn’t.

 

Categories
Counting Number & Operations in Base 10

Kindergarten Counting

cdanielson

(The pretty, blue script is a transcription of the pretty, black script.)

What’s going on here? Is this kid going to do OK in 1st grade? What will the 1st grade teacher have to work with?

Thanks to Christopher Danielson for the submission.

Categories
1.NBT.2 Place Value Uncategorized

Mistake Hall of Fame: Cena

Cena, wherever she is these days, deserves a medal. This video is a classic.

Here we get to see how the teacher followed up with the student, so let’s tackle these questions:

  1. What can we say that Cena does know?
  2. What is going through her head as she answers these questions? Where does she go wrong?
  3. What are the teacher’s moves in this clip? What is her strategy for uncovering the student’s errors?