Course Level
Knowledge Unit
Algorithms and Design
Collection Item Type
Other Material Type

This is a team-based classroom activity using Process-Oriented Guided Inquiry Learning. I use this the first day of CS1, and sometimes the first week of CS2 (depending on students). Teams of 3-4 students work together to identify and evaluate several strategies (algorithms) to solve a Hi-Lo number guessing game. In doing so, they learn about tradeoffs between difficulty and efficiency, and are introduced to complexity analysis, although the activity does not use O() notation.


To learn about effectively implementing POGIL in your CS classroom, check out Clif and Helen Hu's POGIL "Teaching Paper" in this collection. Also see the Facilitator Information in the activity.

Visit the CS-POGIL for more information on using POGIL in your computer science courses ( For general information on POGIL, see The POGIL Project ( Consider attending a 1/2-day or 1-day POGIL workshop or a 3-day POGIL Summer Regional Workshop to learn more about how to effectively facilitate a POGIL classroom and develop effective POGIL activities.

Engagement Highlights

This activity uses Collaborative learning through Process-Oriented Guided Inquiry Learning (POGIL). Additionally, by providing opportunities for interactions with faculty, activities such as these can help to build student confidence and professional identity.

Materials and Links

Computer Science Details

Computer Science Topic(s)
algorithmic efficiency
group work
Programming Language

Additional Details

Prerequisites / Prep Materials

see Facilitator Information in activity

Lessons Learned / Pitfalls

see Facilitator Information in activity

Estimated Time to Complete

1 hour / 1 class period

Material Format and Licensing Information

Material Format
Technology Platform Required
Not Specified/Unknown
Creative Commons License

Author's Institutional Information

Institution Type
Baccalaureate Colleges - Liberal Arts
Community Type
City Midsize