Posted by David Wetzel
These are the top five posts visited during the past week my visitors to this blog.
I would like to thank all the subscribers to my Teach Science and Math Newsletter, new subscribers this week, and all those who visit and find the information useful.
Another week is about to begin and the following are the here are the Top 5:
Teaching Science Using Discrepant Events
Real World Math Problem Solving Videos
Do Plants Drink Cola or Water?
Science Games
Teaching Science Using Mysteries
Posted by David Wetzel

Egg in Bottle Investigation
This is a an investigation into “forces” discrepant event in which students make observations of an event and then explain the science that caused the event.
This simple; however complex, investigation is a great attention getter for learning about forces and atmospheric forces.
May the Force be with You
Materials: (per group)
- One hard boiled egg with shell removed
- One clear plastic or glass bottle that has an opening narrow enough that the egg will not fit through
- One strip of paper about one inch by six inches
Procedures:
- Light the piece of paper with a match and place the paper inside the bottle
- Place the egg in the opening on top of the bottle
- Observe what happens
Expected Observations:
As the paper burns inside the bottle, the bottle will fill with smoke. Shortly thereafter, the students will observe the egg begin to slowly change its shape to fit through the bottle opening as it slides through the opening. Suddenly the egg will fall through the opening and land at the bottom of the bottle.
Questions to Ask Students:
- What did you observe? (Common answer is that the egg was sucked into the bottle.)
- What force or forces caused the egg to enter the bottle? (Common answers include air in the bottle forced the egg inside or gravity pulled the egg inside.)
Science Behind the Discrepant Event
The burning piece of paper heats the molecules of air in the bottle. This causes the molecules of air to move further away from each other. When the flame goes out, the molecules of air in the bottle cool down and move closer together. This is what scientists refer to as a “partial vacuum “. Normally the air outside the bottle would come rushing in to fill the partial vacuum created inside the bottle.
However, the egg is in the way! The “push” or pressure of the air molecules outside the bottle is so great that it literally pushes the egg into the bottle. Gravity causes the egg to fall to the bottom of the bottle.
Discrepant Event Resource
Teaching Science Using Discrepant Events

Posted by David Wetzel

I am starting a new section that will be posted every Sunday - it is called the “Week in Review - the Top 5.” These are the top five posts visited during the past week my visitors to this blog.
I would like to thank all the subscribers to my Teach Science and Math Newsletter, new subscribers this week, and all those who visit and find the information useful.
Another week is about to begin and the following are the here are the Top 5:
Standing on the Moon
Rubric Assessment Tools in Science and Math
Using Google Earth in Science and Math
Teaching Science Discrepant Events
Student Math and Science Games for Kids with ADHD