This site is no longer being updated. Please go to our new site: for the most recent version of these materials.

The ChemCollective   NSDL and CMU


About Us

View Contributors


Papers and Publications


Intro for Instructors

Find Activities

Online Stoichiometry Course

Comment About Your Experience

Share Classroom Data

Modify or Create Activities


Intro for Students

Find Your Instructor's Website

Chemistry Tutorials

Run Virtual Lab

Explore a Murder Mystery

Try Other Activities


Getting Started and FAQ



Related Projects

The ChemCollective >> Instructors >> Find Activities >> Automatically Graded Randomized Problems

Automatically Graded Randomized Problems

We've recently been developing automatically graded randomized virtual lab activities. These problems include random variables and support feedback for common student errors (for example, an automatic prompt when answers are off by orders of magnitude, suggesting that students check to see if they've converted mL to L for calculations.)

Follow the links below to access the activities. Each time the page loads, you will be given a new set of parameters. You will have 3 attempts to solve each problem before you are given the correct answer and asked to reload the problem and try again. Once you have entered the correct answer and completed the activity, you may print the page to be handed in to your teacher.

Like all of our efforts, this is a work in progress. If you have any suggestions for problems to add - or would like to customize one of these problems for your students - please contact us: .


   Page Last Updated: 10.13.2014