Penn Chemistry Learning Assessment and Support System - PennCLASS

What is PennCLASS?

We want you to succeed in General Chemistry at Penn! PennCLASS will help you start your General Chemistry course with basic skills and background material fresh in your mind. It is designed to assess your readiness for the course and provide tutorials only for the material you need to solidify requisite skills before the start of classes. All students enrolled in CHEM 1012 must complete the PennCLASS assessment and assigned tutorials (if any.) PennCLASS will be available through the end of course selection period. Students who earn 95% mastery on their pre-CHEM 1012 topics in PennCLASS by the end of course selection period (1/24) will receive points equal to 3% towards their final grade in the course.

Note: Regardless of AP/IB background, all students - including upperclassmen - wishing to take General Chemistry (CHEM 1012) MUST take the assessment and earn 95% mastery before the deadline on January 24th to earn the 3%.   A list of instructions for the initial assessment phase of PennCLASS and some frequently asked questions are given below.

PennCLASS is for students who are taking Chem1012 and is not for receiving placement out of general chemistry.   Information on the Chemistry Department placement exams can be found here.   

Essential Things to Know BEFORE You Start PennCLASS

  1. It is recommended to start PennCLASS as soon as possible before the start of classes. This will allow you the time to fill in any gaps in your background and ensure you are prepared for the course.
  2. PennCLASS is built around an artificial intelligence-based teaching tool called ALEKS. When you first log in to ALEKS, the system will assess what you know and do not know in General Chemistry and its prerequisites from high school. It will report  the results of the assessment in a pie graph. Once ALEKS determines what you have remembered and what you have forgotten or never learned before, it will teach you only those topics you don’t already know, as long as you are ready to learn that topic.  ALEKS will not try to teach you topics before you are ready.
  3. It is VERY important to complete the initial PennCLASS assessment carefully and honestly! It is the only way ALEKS can determine what you already know and understand (and what you don't!)  If you do this assessment carelessly or answer randomly, you’ll waste time later because ALEKS will force you to work through material you already know and don’t really need to review.  On the other hand, there is no advantage to consulting outside resources – such as a textbook, the internet, or a friend – to improve your assessment score, because then ALEKS will ask you questions that may be too difficult for you.  It is a waste of time to play games with the ALEKS software.  Always read and follow the onscreen instructions very carefully and do the work on your own.
  4. NEVER click the “I don't know” button during any ALEKS assessment unless you really don't have any idea of how to do the problem.  Otherwise, ALEKS will think you don't know a bunch of things you actually do know, take you way back, and make you "learn" them (for example, it may take you back to elementary math!)
  5. The initial PennCLASS assessment will consist of up to 30 problems and should take you no longer than 60 to 90 minutes.  You do not have to complete the assessment in one sitting.
  6. Once the initial assessment has determined what you remember and what you need to learn to be ready for CHEM 1012 (if anything), you will enter a “pie chart learning mode” where you can work to fill in any gaps in your knowledge of the prerequisite material.  If you do well enough on the assessment (i.e. some students may achieve 100% mastery on their first try), you may not have to do any learning in the ALEKS system! Every student will have their own profile, and their own assigned topics and skills to review. When you use ALEKS, you complete the learning tasks you need and not those somebody else needs.  ALEKS provides one-on-one instruction tailored specifically to you.
  7. As long as you earn 95% mastery on your assigned topics by the deadline (January 24th at 11:59 pm) you qualify for the 3% added to your total score in the actual Chem1012 general chemistry class.
How to register for PennCLASS on ALEKS:

ALEKS logo

We recommend that you sign up for ALEKS and complete the initial phase of PennCLASS as soon as possible.   

  • Go to the ALEKS web site.
  • Click on the link marked "SIGN UP NOW" (upper left, below the login box).  There is a $20 fee to register for PennCLASS.  
  • On the next screen, you will be asked to provide the following course code:
    PennCLASS:   LEYT9-D66MH
  • The next screen will ask for information we need to give you credit for your work on ALEKS. Please provide all the information requested. 
  • YOU MUST ENTER YOUR 8 digit Penn ID number (found on your ID card or on PennInTouch).  Click Continue and you should be set to go.
Frequently Asked Questions about PennCLASS and General Chemistry

Q: Is PennCLASS the same as the General Chemistry Equivalency exams? Can I place out Chem1012 with PennCLASS

 A: No. Placement out of CHEM1012 and/or CHEM1022 requires sitting for and passing separate exams offered only during NSO week and the first week of classes in January. Information about the equivalency exams can be found here.


Q: Why do I need to work with PennCLASS and take the initial assessment before the start of General Chemistry?
 A: WE WANT YOU TO SUCCEED IN CHEMISTRY 1012!! CHEM 1012 is taught at the level of a university science course - i.e. at a high level and fairly fast pace. The instructors will assume that all students have a solid background from their high school chemistry and math classes. The initial PennCLASS assessment will determine areas in which you need a little (or a lot) of refreshing to ensure you are ready at the start of the class.


It may be necessary for you to review old material or even learn some new material prior to the start of CHEM 1012. Students come to college chemistry with a variety of backgrounds and levels of preparation. After the initial assessment, PennCLASS will tutor you in ONLY those areas in which you may need review.


 Q. Will I get a grade on the initial assessment in PennCLASS?

 A. NO! The initial assessment (60-90 min) is only to determine what background material needs review. There is no grade given.


 Q. What’s the deal with the 3% towards my grade?
 A. To encourage you to use PennCLASS before you actually need the skills, students who complete all the topics by the end of course selection period will earn points equivalent to 3% of your grade in Chem1012.  
 Q. What is a “good score” on the assessment? The assessment said I need help with 60% of the topics…is that bad?

 A. Scores on the initial assessment are VERY hard to interpret. Many students need just a little refresh on many “easy” topics, and will finish the tutorials very rapidly (several per hour.) Other students may get a 90%, but the remaining 10% are topics they never covered in high school. Mastery of new material may take longer.


 Q. How much time should I expect to spend mastering the topics after the assessment?

 A. This will vary widely depending on how many chemistry, science, and math classes you took in high school, and how recently you took those classes! We estimate 15-20 hours (spread over a month!) is a typical range, but some students may need significantly more time. REMEMBER: whether or not you spend the time before January 24th, the ALEKS diagnostic is a very good indication you will need to work on all those basic skills to do well in General Chemistry. Why not start the semester ready to succeed from the start?


 Q. Can I email someone in Chemistry or my pre-major advisor with questions about my initial PennCLASS assessment?

A. We recommend you spend at least 3-4 hours in tutorials AFTER the initial assessment before consulting with an academic advisor.  As described above, we can't offer much advice based only on the initial assessment without seeing how quickly or slowly you are able to review at least some of the topics.  Almost all students find the tutorials easy and helpful once they get started and realize they can fill in their remaining background gaps by January 24th without an unreasonable effort.   


Q: What topics will be covered on the pre-Chem1012 assessment?
 A: The general topic areas in PennCLASS are listed below:

• Math and Algebra (not Calculus)

• Measurement – SI Units, unit conversions, dimensional analysis

• Matter – mass, volume, density, atomic theory, the elements

• Atoms, Ions, and Molecules – atomic structure, molecular and ionic compounds

• Stoichiometry – moles, molar mass, equations, reaction and solution stoichiometry

• Gas Laws – basic gas laws and the ideal gas law

This material can be found in your books from high school classes, or in Chapters 1-5 of the Chem1012 textbook, "Chemical Principles" 8th Ed. by S. Zumdahl.