The Egg Drop

This rich example includes both a description of teaching and an assessment task. Mr. S. has students engage in a full design activity, designing and testing a container that can prevent an egg from breaking when dropped. The technology activity was preceded by a science unit on force and motion so that students were able to use their understanding of science in the design process. He has carefully considered commercially prepared versions of this activity but modified them to create one based on his experiences and the needs of the students. He has considered the safety of the students. The use of the videotape of former students not only provides a local context for the activity, but provides students with ideas about the designs that work and do not work. After the enjoyable day, Mr. S. requires students to reflect on what they have learned and apply it to a new, but similar problem.

[This example highlights some elements of all of the Teaching Standards(A; 5-8 Content Standards B and E; Program Standard D; and System Standard D.]

As Mr. S. reviewed his syllabus for the year, he saw the next unit and smiled. On Monday they would begin the "Egg Drop"--the students, working in teams, would design a container for an uncooked egg. The time was right. During the period between the winter break and the new semester, the students had focused on the similarities and differences between science and technology. At the beginning of the second semester the students had completed activities and engaged in discussions until they demonstrated an adequate understanding of force, motion, gravity and acceleration. Now it was time to bring the knowledge of science principles to a design problem. The problem was to design a container that could be dropped from the second floor balcony without breaking the egg.

Some variation of the egg drop activity was found in just about every middle school science book that Mr. S. had ever seen. But over the years he had come to know what worked and what didn't, where to anticipate the students would have difficulties, and just how to phrase questions and challenges the students could respond to without being overwhelmed. He had developed some aspects of the unit that were special to him and to the students in Belle Vue Middle School. He knew when he introduced the idea that at least one student would have a tale to tell about dropping a carton of eggs when carrying groceries home from the store or when removing the carton from the refrigerator. While dropping eggs from the balcony was not part of the every day experience of the students, dropping things and having them break was.

On Monday, he would set the challenge, the constraints, and the schedule. They would begin with a whole class review of what the students knew about force, acceleration, and gravity and the design principles. He would have someone write these on a chart that they could hang on the wall during the unit. Next they would identify things they had seen fall gently without breaking and about the size, shape, material, and construction of these items. Finally he would tell the students the constraints: teams would be made up of three students each; materials would be limited to the 'stuff' available on the work table; teams would have to show him a sketch before they began building their container; they would have to conduct at least two trials with their container--one with a plastic egg and one with a hard-cooked egg. For years, he had collected odds and ends--string and plastic, paper towel rolls end egg cartons, Styrofoam peanuts, cotton and other packing material. In the world outside of school, limited availability of materials was a real constraint. He was grateful that he taught in Florida where he could open the door and watch the students outside as they climbed to the second floor balcony to conduct their trial runs. He knew that if he taught up North, where they would have to do this activity from the gym balcony, he would have to plan differently as the class would have to move to and from the gym.

On Tuesday, he would have a few raw eggs for each class. He would have several students try to crush them by exerting force with their hands. He would need lab aprons, goggles, and plastic gloves for that. Then he would show the egg drop video. After the first few years, he learned to videotape the class on the day of the egg drop. He had edited a short video of some of the more spectacular egg drops--both successful and unsuccessful. The students enjoyed watching older brothers and sisters, and famous and infamous students. The students would then get into their groups and discuss the features of the containers in which the eggs broke and those in which the eggs did not break. He would challenge them to consider how they might improve the successful egg drop containers. Toward the end of the period, each group would have someone report to the class one thing the group had learned from the video and discussion.

Wednesday would be an intense day as students argued and sketched, sketched and argued, had plans approved, collected materials, bartered with other teams for materials, and tried to build a prototype of their container.

Thursday they would begin class with a discussion of why they needed to build a prototype and why they needed to do some trial runs with plastic and hard cooked eggs. He would ask them the advantages and disadvantages of using the plastic and hard cooked eggs in the trial runs. This would give them an opportunity to consider cost and the characteristics of models. There would be time in class to work and some groups would be ready to begin the field trials. He would need a supply of trash bags to use as drop cloths.

Friday's class would begin by reminding the students that the assessment for the egg drop would not be whether the egg broke, but rather how they would be able to share what they considered as they tried to solve the problem of designing a container for an egg so that the egg would drop 15 feet and not break. He would also remind them that the egg drop was scheduled for Wednesday, ready or not.

Monday would be an uninterrupted work day. On Tuesday they would by work in their groups to determine what would be needed to make their egg drop event a success. In his plans Mr. S. noted that he would need a set-up team that would cover the ground below the balcony with trash bags. A clean up crew, again wearing plastic gloves, would gather the bags and get them into the disposal. He anticipated that they would want two class mates to have stopwatches to measure the time it took for the egg to drop. The students would want to determine where the egg should be held for the start of the egg drop. There were always heated arguments about whether the starting line was from the arm of the dropper or from some point on the container. They would need someone to call "Drop!"

Wednesday would be the day of the egg drop. Thursday, the class would begin by meeting in their small groups to discuss what worked, what didn't, why, and what they would do differently if they were to do the egg drop design experiment again. Then they would discuss these same ideas as a whole class.

Friday, the students would fill the board with characteristics of good design procedures. Then they would write and sketch in their notebooks these characteristics and what each had learned from the egg drop activity. He knew from experience that the egg drop would be an engaging activity.

The "header titles" emphasize some important components of the assessment process.

SCIENCE CONTENT: The Content Standards for Science and Technology for students in Grades 5-8 call for them to understand and be able to solve a problem by using design principles. These include the ability to design a product; evaluate technological products; and communicate the process of technological design.

ASSESSMENT ACTIVITY: Following the egg drop activity, students each prepare a report on one thing they propose in order to improve their team's container and how they would test the effectiveness of their improvement.

ASSESSMENT TYPE: Individual. embedded in teaching.

ASSESSMENT PURPOSE: The teacher will use the information to assess student understanding of the process of design and for assigning a grade.

DATA: A report, written, sketched, or both, in which students describe an improvement to the container, the anticipated gains and losses from the improvement, and how they would propose to test the new container.

CONTEXT: The egg drop activity allows students the opportunity to bring scientific principles and creativity to a problem, while developing the skills of technology and having a good time. However, the excitement of the activity can overshadow the intended outcome of developing understanding and abilities of technological design. This assessment activity provides the opportunity for students to reflect on what they have experienced and articulate what they have come to understand. The activity comes after the design of an original container, the testing of that container, a class discussion on what worked and why, what didn't work and why, what they would do differently next time, and an opportunity to make notes in a personal journal for science class.

EVALUATING STUDENT PERFORMANCE: Student progress in understanding and doing design can be evaluated by comparing the student responses in the reports with the list generated by previous classes. The astute teacher will have made sure that the list included constraints such as cost, time, materials, and trade-offs. Criteria for a quality report might also include how well the student has differentiated between the design and its evaluation. The teacher might also consider the clarity of expression, as well as alternate ways used to present the information, such as drawings.