Drawing Appropriate Conclusions

DRAWING APPROPRIATE CONCLUSIONS: Are girls stronger than boys?

Seventh-grade Life Science, one 50minute period

Purpose: Students will perform individual experiments and record results as a group. They will then draw conclusions about the trends observed in the results.

Procedure: Students are divided into three groups according to height. Each student will face the wall with a chair in front of them, bend over so that their head touches the wall and their back is perpendicular to the floor, they will then attempt to lift the chair and stand. They will record their results (yes or no) on the corresponding chart. Once all the data is collected, students will analyze data and draw conclusions.

Questions: What trends, if any, do you notice? Can boys and girls both lift the chair? Does height have any relevance?

If No: This is a good example problems you may encounter while doing your science project. 1. There are not equal numbers of boys and girls. 2. This is not a big enough test group. 3. Students are roughly the same age.

What is supposed to happen is that boys are unable to lift the chair

Questions: Why would this be true? Is it because girls are stronger than boys? [hint] What is the purpose of bending over to lift the chair? Where is your weight distributed?

Part of your weight is in front of you instead of over your feet – So why are girls still able to do this?

How do we know this? This is due to where their center of gravity is – boys have a center of gravity in their chest, while girls have a center of gravity in their hips. The chair experiment is designed to show you where your center of gravity is.

Center of gravity is found by distribution of mass. If you have concentrated mass in your chest, your center of gravity is in your chest; if your mass is concentrated in your hips, your center of gravity is in your hips.

Examples using cars: Suzuki Samurai, Hum -V