When families look for a hobby that they can all do together, historical re-enactment is a viable choice. The Civil War, Revolutionary War, Viking, medieval and renaissance eras are fun places to spend the weekend and all require "period" lodgings for the duration of weekend-long events. Every component of historical tents must be convincingly recreated, including ropes and rope tensioners. You can make your own rope tensioners that will keep your period tent upright and secure in any weather out of any number of materials that can suit the reenacted era.
Drill a toggle tensioner. Take a 2 inch long piece of dowel at least three times thicker than your chosen rope and drill two holes at roughly 1/3 and 2/3 of the way down the dowel's length through the cylinder side. The holes must be big enough for your ropes to pass through. Sand the holes so splinters don't damage your rope. Thread the rope end down through one hole and up through the other. Tie a knot in the end of the rope to keep the tensioner on. For a more authentic, less dowel-like look, paint some wood stain on your tensioner.
Cut a leather tensioner. For smaller tents or ones that do not need to withstand high wind gusts, a rope tensioner made of a tab of leather will work. Cut the leather into a 1 inch by 2 inch rectangle or oval with heavy scissorss, and snip two holes larger than your rope into the leather. Add brass grommets by fitting the grommet front and back through the hole and pounding into place with a grommet stamp. The grommets provide hole reinforcement. Thread the rope through the tensioner as above.
Carve your own tensioner. If you are handy with a carving knife, eschew the dowel and carve your own tensioner from a piece of wood. Shape the wood to roughly 1 inch wide, 2 inches long and, again, at least three times the thickness of your rope. Carve out two proper sized holes at roughly 1/3 and 2/3 of the way down the tensioner's length. Sand the entire piece to prevent splinters, and stain if you wish. Thread the rope through and tie as above.