Home school resources, specifically focused on getting started in Texas:
Texas Home School Coalition Association
This organization provides support to all Texas homeschooling families. Whether you need information about where to begin, legal questions or support, or need resources such as curriculum or high school requirements, it can all be found here.
Texas Essential Knowledge and Skills (TEKS)
These are the state standards that guide all educational institutions whether you are public or private in regards to what your child should know and be able to do at each grade level. This should guide your instructional plans and goals as these will be the norms your student will need to master when you decide to begin testing.