I’d recommend she reach out to members of the North Texas Blacksmith Association - that’s probably a better fit for a one-off, non-member minor looking for blacksmithing on a very short-term basis.
NTXBA Web site (but Facebook page is more active): http://www.ntxba.org/
They had a Forge-In at Texas Farrier Supply in Kennedale last night
There is an Open Forge class this Sunday morning (https://calendar.dallasmakerspace.org/events/view/13538), but it is for members only and minors would need to be accompanied by an adult (and it’s gonna be quite hot). Joining with a Family Membership for a month just so he (and she) could attend would likely not be the best solution.
Another Thing To Do
If actual blacksmithing doesn’t work out, a trip to Texas Farrier Supply might still be a good idea: they have a fair amount of knife-making supplies (steel, tooling, exotic wood and other materials for knife handles, et al). They are open M-F 8-5.