misconceptions/discrepant events

Measuring Activity

I want to share a measuring activity for you to consider. First, start with two baseballs. The first baseball is a regular baseball. The other baseball is called a ". Next, get six to eight students to volunteer. Without talking at all the students must hold the normal baseball and the small ball. They then must decide if the normal ball has more, less or the same mass as the small ball.

Modeling the Concept of Ionic Bonding

When describing abstract concepts like chemical bonding, it always seems to feel far too easy for both teachers and students to resort to the “wants” and “needs” of atoms. After all, we understand what it means to want, need, or like something, so it often feels appropriate (and easier) to use a relatable metaphor or subtly anthropomorphize these atoms to accommodate our students’ current reasoning abilities. While predicting the types of bonds that will form and the general idea behind how atoms bond can be answered correctly using such relatable phrases or ideas, the elephant in the room still in remains—do our students really understand why these atoms bond? 

Demonstration: Reaction of Magnesium and Silver Nitrate

I found a version of this demonstration online a couple of years ago. I admit, when I first tried it with my class it was mostly for a crowd pleaser to demonstrate the activity series of metals, but I then became very intrigued by the processes occurring. The original source only referenced the “single replacement reaction” between Mg(s) and AgNO3(aq). Therefore, when I saw a grayish product (silver) I was not surprised. However, I was surprised by the white flash and the production of a white product, which were reminiscent of the classic combustion of magnesium demonstration. This led to some research and my conclusions that follow. Read through to the end and you will find a video of the demo.

Misconceptions and Struggles with Double Displacement reactions and dissolving...

Looking over my student's papers, there may have been more misconceptions created because of the way I planned the curriculum. In all of the experiments students can see and observe that not all of the crystals or material dissolves yet the water starts to conduct. In their minds there is evidence that they believe either something DOES dissolve or it does NOT. Clearly, partial dissolving is initially too much to consider.

The Dry-Ice-in-Water Cloud

Have you ever wondered where the cloud comes from when dry ice is placed in water? If you think the answer is “atmospheric water vapor”, be sure to read this post because experimental evidence suggests that this explanation is wrong.

Is there more to formative assessment than "Get it or Don't"?

In teacher preparation, the Vygotsky based theory of formative assessment is integral because teachers and teacher educators who recognize their knowledge as knowledge in formation are better prepared to recognize the value of students’ knowledge. After all, most learners find it easier to build upon prior knowledge when learning material as opposed to having the material dissociated from prior experience and viewed as a completely new and isolated material.