They asked what’s allowed, listing different actions. Throwing stones and holding rallies is permitted, he said. Throwing firebombs is a “maybe” and using knives a definite “no.”

Such workshops — held amid weekly mass marches on the border for the past month — are the latest sign of the Hamas militant group’s search for new tactics for breaking the debilitating blockade of Gaza. Israel and Egypt closed the borders after Hamas overran Gaza in 2007, and Israel blockades the sea and controls the skies, making it increasingly difficult for the group to govern.

The border protests were the idea of grassroots activists several months ago, and the project, envisioned as non-violent, was quickly embraced by Hamas. The militant group has…