Standardized Testing Practice (students)
Here is a collection of sites that students can use to practice for various standardized tests, such as the M-STEP and SAT.
M-STEP Practice (students)
Here are some resources for practice for the M-STEP.
There preview link (above - Are You Ready for M) is intended to provide students and teachers with a brief look at the English language arts (ELA), mathematics, science and social studies technology-enhanced item types. (updated April 2016)
The link above connects to practice problems for Math & ELA online standardized assessments. This is a great resource for preparing for the M-STEP and other standardized assessments.
I found a collection of iPad apps that can be used with 1st-8th graders. It has questions that are based on grade level curriculum (common core). It appears the first 3 levels are free to use and then locked.
PSAT/SAT Practice (students)
Michigan Electronic Library offers some great resources. Here is a link to the Learning Express. Students can create an account in order to save their work. The School Center contains a College Prep area for PSAT/SAT Practice.