There are three different worksheets that practice the math students are likely to see on the Virginia Chemistry SOL. Each version is slightly different but covers the same concepts. Students can be grouped into three students/group and work together to complete the problems. Once completed (or after a certain time) the students with the same worksheets can then get into larger groups to compare answers. I have a pdf of the answers if you are interested I will send them via e-mail (firstname.lastname@example.org).