BACKGROUND:

A scientist must learn to accurately describe objects that he/she is studying. A glass of water, for instance, might be described as a "clear cylindrical container, of 250 ml. capacity containing about 200 ml. of a clear, colorless, odorless liquid of unknown identity."

First graders do not yet have the vocabulary to make that detailed a description, but they can begin to use words that describe shape, size, color, smell, and feel. They can also begin to understand that "big" and "little" are good descriptive terms, but sometimes additional measurements are necessary. Measurements help us distinguish between a big elephant and a big house.

In this activity, students will measure their own height and weight in either metric or English (depending on your comfort level). (Metric measurement is strongly recommended). Parent volunteers able to help students with this lab are ideal.

PROCEDURE:

1. Request from parents prior to lab, the use of bathroom scales.
     
2. Record all the students name on the worksheet provided. Put the date for each of the weight and height. You will redo this exercise 6 months later to have students see if they have grown.
     
3. Give each group of students a ruler and a tape measure. Set-up stations in the classroom with the bathroom scale. At each station students will measure their weigh and record it on the sheet next to their name.
     
4. There are several ways in which students can measure their height. You can have one student that is to be measured to stand with his/her back tot he wall. The other student should make a tick mark with the pencil horizontal with the head. Illustrate how to do this with children. You can either have them measure the tick mark by using the ruler and figure out how to add the rulers or you can have a pre-measured wall. 
     
   With a metric ruler or meter stick mark centimeter increments on the paper. You may want to have students also measure in the English system.
     
5. Students should weight themselves first. You may have a difficult time to find a metric scale in the United States, so you may use pounds. Make sure the students read the scale with the aid of an adult. Students will need guidance on how to read the scale. Write the amount on a piece of paper and tell the student that they will record the weight next to their height on the butcher paper.
     
   After all the students have been weighed and measured have the students predict whether they will grow and gain weight in the next several months. Roll up the large sheets of paper and save these with the student's lab sheets for several months. In 3-6 months repeat this lab and model how to do the conclusion. This lab works well if done at the beginning of the year and then again at the end of the year.