סביבת אליס – שיקולי הפיתוח של הסביבה, חומרי לימוד לתלמידי תיכון Stephen Cooper Stanford University 2 July, 2012

Overview Background – declining CS enrollments Past and Present work with Alice –Program Visualization –Description of Alice –Demo –Results from NSF studies –How Alice is being used Alice Support for teachers Future work with Alice –Alice 3.0 Q&A

US National Science Foundation support for Alice work NSF – CCLI EMD Proof of Concept NSF – ATE NSF – CCLI Project NSF – ASA NSF – CCLI Level 2 NSF – ITEST NSF – CCLI Phase 1 NSF – CISE special project NSF – ITEST Scale-Up NSF – CCLI Level 2

Background Declining student enrollments High attrition in introductory computing classes

The Shrinking CS pool Women and minorities are making up an increasing percentage of undergraduate student populations According to the Taulbee survey, the total number of students dropped to 1% in 2005, and held steady at 1% for

Attrition in introductory computing Dropout rate in first year –Informal surveys: 30 – 70% –Typically 35 – 50 % –Especially high for women and minorities (women receive fewer than 20% of the Bachelors degrees in computing) In 2011, the number was 12% (see the Taulbee survey for more details)

Why? Possible reasons Adding object-oriented concepts to first year courses has increased the number of topics to be covered. – increased teacher prep time – increased student frustration The way we teach programming has not really changed in the past 25 years

Game Plan Develop an innovative instructional approach to develop intuitive understanding of –Fundamental programming concepts Sequence Decisions Repetition Methods and parameters –OOP concepts objects and classes encapsulation methods and parameters inheritance

Visualization in CS The use of graphics in teaching CS concepts has taken three major forms: –Algorithm Animation –Simulation –Program Visualization

Program Visualization Program visualization allows a student to write a program and view a visual representation of execution Primary use has been for introducing math and programming concepts Examples: Logo, Karel the Robot

The Alice Software A 3D interactive animation environment A program visualization tool –The program state is visible to the student –State changes are animated A tool for teaching fundamental programming concepts – object oriented

Alice features Uses 3D graphics to engage students Has a “smart” drag-and-drop editor that prevents syntax errors Appeals to wide audience – Storytelling (young women, minority students) – Interactive computer games (young men)

Alice Features Makes objects something students can see and relate to Has a java syntax mode to ease the transition to C++/Java/VB.net

Our pedagogic approach Emphasize design using storyboards Program objects-early or objects-first –Agnostic with respect to the early introduction of classes Allow an (optional) early introduction to events

Alice Demo

Alice language features Objects are stateful, but manipulation of state is limited to a set of primitive functions –Challenges of teaching state transformations and functions Separation of the functional and imperative aspects of the language, like Algol –Algol "is a language so far ahead of its time, that it was not only an improvement on its predecessors, but also on nearly all its successors“ (Tony Hoare)

NSF Proof of Concept study: High Risk Students We examined historical data at Ithaca College and Saint Joseph’s University for 5 years Found that –Percentage of women in CS classes is typically low –Students at high risk of DWF Have little or no previous programming experience Are not ready for calculus

Results of Proof of Concept study As used towards retention of CS majors – GPA in CS1 improved Grades went from C to B at-risk students (students with little to no prior programming experience and/or weak mathematics background) – Increased retention into CS2 from 47% to 88% – Improved attitudes towards computing

Completed NSF-sponsored Alice (education) projects Proof-of-concept –study of the use of 3D animated program visualization to introduce programming concepts to high risk students CCLI Project –Extend study to other colleges & universities with varying student backgrounds, demographics, courses ATE –Modify approach for community college environment & students

Current NSF-sponsored Alice (education) projects CCLI level 2 –Combining Alice with Media Computation (developed by M. Guzdial at Ga. Tech) in CS1 ITEST –Providing professional development and assistance to high school and middle school teachers in 6 regions with incorporating Alice into their curricula ITEST Scale-Up

Current NSF-sponsored Alice (education) projects ITEST –Results from pilot in Va Beach More than tripling of students taking intro to computing class Tripling of students taking AP CS A Interesting anecdotal results with students having high-functioning forms of autism –Current (ITEST Scale-Up) 750 HS and MS teachers (in NC, SC, MS) K-12/higher education partnerships

How Alice is being used In pre-CS1 – course for majors and students considering a CS major As a conceptual introduction in CS1 The Introduction to programming course – non-majors – attract students to become CS majors In computer literacy – problem-solving component In Pre-AP in high schools In various capacities at middle school

Alice usage In any given term, ~200 colleges are using LTPWA) Alice has been likely used in > 1000 high schools (self-reporting) Increasing adoption in UK, Costa Rica, Brazil, Taiwan and other countries

Alice support for teachers Websites with access to curricular materials Alice teacher professional development (generally in summer) Alice teacher communities (

Where to go for curricular ideas – ols/ ols/ There are several others: – –etc.

What you’ll find –Sample syllabi –Solutions to chapter exercises/projects –3D Models –Sample student projects –Sample tests

Strengths –Complete and organized courses/curricula –Materials are often used “as is” –Appropriate for college and HS Weaknesses –Not as usable for younger students –Not ready for informal education

What you’ll find –Tutorials (but not stencils) –Videos of Alice worlds –Example worlds

Strengths –Excellent start-up materials –Useful for middle and high school –Good for informal education Weaknesses –Many of the tutorials are not problem- based – they tend to focus more on the mechanics of how to do something –The teacher still must incorporate these materials into a course/unit/lesson

Future Alice versions Alice 3.0 –Includes (EA) SIMS 3D models And their (the Sims’) existing primitive animations As will include many useful primitives such as walk and touch –Has the ability to generate Java code –Provide its own Java IDE (within Netbeans) –Available from

Demo Alice 3

Questions? Steve Cooper