If you look at the following section it lists some instructional activities that are exempt. It would fall under non amusement instruction.
Like stated previously, if you start to sell items, ie holsters, purses, or other CHL gadgets or tools then you get into the realm of retail sales, and that portion of your business is subject to sales tax.
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(2) Nonamusement services--Activities that are primarily instructional in nature, or nontaxable personal services. Places, services, and clubs that the tax on amusement services does not cover include, but are not limited to:
(A) hobby clubs (stamp collecting clubs, toastmaster clubs, camera clubs, amateur radio clubs);
(B) instructions for any sport or musical discipline;
(C) camps for children (day camps or boarding camps);
(D) video cassette clubs;
(E) political fundraisers;
(F) campground admissions;
(G) cruises that last longer than 24 hours and extend offshore beyond Texas territorial limits;
(H) fishing and hunting leases and guide services; and
(I) membership in sororities and fraternities.