Do gummy worms have a high tensile strength?

No, because you can pull them apart. Materials like steel, that cannot easily be pulled apart, have a high tensile strength.

The tensile strength of a material is the maximum amount of tensile stress that it can be subjected to before failure. Having what can I think can best be described as a rubbery consistency, gummi worms (the Word gummi comes from the German for 'rubber') can be easily pulled apart by hand and therefore have a very low tensile strength.