Lesson 3
Part 1

Just Passing Through: Designing Model Membranes

Exploring Membranes (1) / Grade 5 / Jersey City, NJ

The EIE Curriculum

EiE - Just Passing Through: Designing Model Membranes, L3 Part 1

Students explore properties of natural membranes and test the performance of several model membrane materials.

Reflection Questions

What evidence do you see that Marlene's students are developing an understanding of the properties of membranes through their explorations?

Marlene's students make observations and comparisons related to what they see, and create well-supported explanations for what they have noticed. 

  • A student comments that it looks like raisin number 3 is trying to grow (possibly referring to the fact that the water is plumping up the raisin). (5:15)
  • When asked what he noticed about raisin number 4 in comparison to the others, a student points out that it was still dark and a bit hard. Another student adds that the raisin was small, like raisin number 1. (11:30)
  • When thinking about what would happen if raisin number 4 was left in water for a longer period of time, students suggest the raisin would be bigger, hinting at the idea of membranes controlling rate of flow. (12:40 and 13:15)
  • A student suggests the dirt and sand might not be able to move through the membrane because they're too big and the water and air particles can move through the membrane because they are smaller. (15:25)

Several times during the reflection portion of this lesson, Marlene uses a Turn and Talk strategy and has students discuss a question in their small groups. What evidence do you see that this strategy helps push students' thinking?

Turn and Talk allows students to share new ideas and draw conclusions in a low-stakes setting before presenting ideas to the class. 

  • Marlene asks students to predict what would happen if they left raisin 4 in the water for the same amount of time as raisins 2 and 3. Students use what they've observed to form an explanation. (12:10)
  • Marlene has students talk in their groups about how the water got into the raisins when there were no holes that they were able to see. This requires students to think critically and create an explanation based on what they have observed. (14:20)