Educators' Science and Mathematics Institute Series

Winter Ecology Lesson Plan

Descriptive Title:  Snow Crystals

Submitted By:  Karen Abata

Subject and Grade Level:  Earth Science 9

Overview/Purpose:

The structure of snow crystals is determined by the temperature of the air in which crystals form and the humidity of the air through which it travels.

Determine the relationship between the type of snow crystals that form and the air temperature and relative humidity

Objectives (Learner Outcomes):

Identify the basic hexagonal structure of snow crystals and recognize the variation in the crystal structure

Collect snow crystals with observable structure

Measure air temperature and relative humidity

Use data to relate snow crystal structure to temperature and relative humidity.

Activities and Procedures:

Collect snow crystals on black velvet board or black construction paper.  Boards should be frozen so crystals do not melt.

Observe crystal structure with had lens, or magnifying glass.

Create permanent record of snowflakes on microscope slide fixed with hairspray (handout from Don Weiss).

Measure and record air temperature and relative humidity

Repeat several times under different weather conditions

Determine relationship between type of crystal structure and temperature and relative humidity.

Closure:

Practical application-physical development of crystals can be related to many aspects of Earth Science.  

Helps understand dynamics of cloud formation, precipitation and weather systems.

Help recognize that factors of temperature and humidity are important.

Assessment Strategies:

Students will describe snow crystals structures and explain how the structure is determined by temperature and humidity

Lab procedures and data analysis

Materials:  

Black velvet board

Microscope slides

Standards Addressed:

Construction new knowledge (science)

Using scientific knowledge in Earth Science (science)-atmosphere and weather

Data analysis (math)