Do you feel like when you assign physics/chemistry problems for homework that the students simply copy from other students that understand the material?
ScienceDroid.net is a website that I have created that generates a unique set of problems for each student to complete for homework. In addition, it also automatically grades their homework and sends the student an email with their results.
Teachers receive the students given data, responses, and results in a separate, easy to read spreadsheet.
This a 21 day trial of the paid version. The full/paid version will not be available until January 2017. You can test it out and then fill out the contact form and I will email you when the paid version becomes available.