Free Praxis exams are available through some universities and via websites such as Mometrix.com and Test-Guide.com. It's also possible to access some free Praxis materials, including practice tests, on the ETS.org site as of 2015.
Wisconsin Lutheran College offers free Praxis tests. The practice tests include an all subjects option as well as writing, reading, math and content knowledge tests. In addition to the actual exams, the uploads offer test-taking tips and other strategies for passing the test.
Mometrix.com is a website for Mometrix Test Preparation. The site offers free core practice tests for math, reading and writing. The site also includes videos that help test takers review for the tests. More test preparation materials are available for purchase through the site.
Test-Guide.com features several practice tests for reading, writing and math. The writing tests assess specific skills, such as improving sentences and identifying errors. The site randomizes the math practice tests, allowing site visitors to take them numerous times.
Education Testing Services produces the Praxis tests. The website offers a few free preparation materials, including practice tests. ETS.com also has other test preparation materials available for purchase.
ETS has designed the Praxis Series of tests to assess teacher candidates' knowledge and skills for potential licensure. The tests include the core academic skills as well as subject-specific content.