Why Is The Sea Salty?
Submitted by:Pam Hansen and Christy Bingham Cleveland Elementary School,
Cleveland, UT
Endorsed by: These lesson plans are the result of the work of the teachers who have
attended the Columbia Education Center's Summer Workshop. CEC is a consortium of teacher
from 14 western states dedicated to improving the quality of education in the rural,
western, United States, and particularly the quality of math and science Education. CEC
uses Big Sky Telegraph as the hub of their telecommunications network that allows the
participating teachers to stay in contact with their trainers and peers that they have met
at the Workshops.
Date: May 1994
Grade Level: K-3; Science/ Art
OVERVIEW:
In preparing for an ocean unit, do a 'K W L' organizer. 'K' is for what we know about the
ocean. 'W' is for what we want to learn about the ocean. 'L' is for what we
have learned about the ocean. The following lesson was developed because the
students wanted to know why the ocean is salty.
PURPOSE: For students to observe how salt concentration increases in water.
Also, how the salt remains after the water evaporates.
OBJECTIVES: The student will be able to explain why the sea is salty.
RESOURCES/MATERIALS:
Rock salt, water, containers, strainers.
Book: Oceans, Instructional Fair, Inc., Grand Rapids, MI
ACTIVITIES AND PROCEDURES:
1. Students pour water over the rock salt which is contained in a strainer.
The water plus dissolved salt will be collected in a plastic cup. Students will
taste the water sample.
2. Students will allow the water to evaporate, observing that the salt remains.
3. The above procedure is repeated over a 3 or 4 day period. The students will
observe that the salt increases each time new water is added.
TYING IT ALL TOGETHER:
Students will do a Saltwater Painting to once again observe the
evaporation process. Mix warm water, salt, and food coloring. Paint pictures
with the mixture on white paper. Let dry. The water evaporates, but the salt
remains, creating beautiful pictures. Also included on Big Sky is a script for
an ocean program. It is entitled "Under the Sea". ** (see 'CECmisc.47'
lesson)** This is a good culminating activity for an ocean unit.
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