Great Green Globs Contest

submitted by: Ihor Charischak
on June 15, 2005


Course: Math Grades 6-12

Topic: Graphing Functions

Resource type: Tool

Catalogue entry:

Resource location:

Story: Green Globs was originally developed in the early 1980's by Sharon Dugdale and David Kibbey at the University of Illinois to create a software environment that combines tool exploration with an engaging context.

At one time I had a student ask me why he needed to learn about slope and y-intercept forms of equations. I responded by saying that two weeks from today we will be going to the lab for the Great Green Globs Contest and the better you know slopes and y-intercepts the better you will do in the contest. My comment surprised and intrigued this student. (He eventually would go on and come in 2nd in the contest.) Sometimes games can do more for students than any ominous threat of an upcoming test.

Doing the activity: During the next two weeks students prepared for the contest by playing globs as often as they could – mostly on their own time since computers were scarce in schools.

On the day of the contest the students were given a saved game so that everyone worked on the same array of Globs to see who got the highest score in the time period allowed. They also had to record their equations that they used on a log sheet that was provided for them.

See for details on the contest.

Debriefing: Most of the students got very good at graphing linear functions after the globs experience. What was the big surprise for me was that many of the middle school students continued to play the game not at the novice level, but at the advanced level and demonstrated an ability to manipulate functions that they wouldn’t normally see in the curriculum until their second year of Algebra.

In my current Matrix project work in Elizabeth we had several students work on Globs. Here is an example of what one 8th grader did with it:

Now Guillermo is a very talented math student so maybe what he did wasn’t so surprising. But what was more remarkable is that he became a teacher for several other students who wanted to learn how he got his high score.

Here was some of their results:

It doesn’t get any better than this!

Related math tool: Shooting Balls

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