Under Texas state law, homeschooled students are allowed the same access to PSAT/ACT/AP testing as public school students, and must be charged the same testing fee as district students. 

According to the Texas Education Code, Section 29.916:

Sec. 29.916.  HOME-SCHOOLED STUDENT MERIT SCHOLARSHIP AND ADVANCED PLACEMENT TESTING.  (a)  In this section:

(1)  "Home-schooled student" means a student who predominantly receives instruction in a general elementary or secondary education program that is provided by the parent, or a person standing in parental authority, in or through the child's home.

(2)  "PSAT/NMSQT" means the Preliminary SAT/National Merit Scholarship Qualifying Test sponsored by the College Board and Educational Testing Service and the National Merit Scholarship Corporation.

(b)  A school district shall permit a home-schooled student entitled under Section 25.001 to attend public school in the district to participate in an administration of the PSAT/NMSQT or a college advanced placement test offered by the district.  A school district shall require a home-schooled student to pay the same fee to participate in a test under this subsection that a student enrolled in the district is required to pay.

(c)  A school district shall post on an Internet website maintained by the district the date the PSAT/NMSQT will be administered and the date any college advanced placement tests will be administered.  The notice required under this subsection must state that the PSAT/NMSQT or the advanced placement test is available for home-schooled students eligible to attend school in the district and describe the procedures for a home-schooled student to register for the test.  A school district that does not maintain an Internet website must publish the information required by this subsection in a newspaper in the district. If a newspaper is not published in the school district, the district shall provide for the publication of notice in at least one newspaper in the county in which the district's central administrative office is located.  The information required under this subsection must be posted or published at the same time and with the same frequency with which the information is provided to a student who attends a district school.

(d)  The commissioner may adopt rules as necessary to implement this section.

Texas state law requires all school districts to allow homeschooled students to register for PSAT and AP testing taking place in their district.