Coarsely chop about half the strawberries, to equal 1 1/2 cups chopped berries (reserve remaining ones for garnish). In a 2- to 3-quart pan over medium heat, stir chopped strawberries, sugar, and gelatin until gelatin and sugar are dissolved and mixture is boiling. Remove from heat and stir in yogurt, vanilla, and orange peel until well blended (chunks of strawberries will be visible). Pour into pie crust.
Chill until set, at least 6 hours, or cover with plastic wrap and chill up to 1 day. Just before serving, sprinkle chocolate chips evenly over top of pie. Slice remaining strawberries. Cut pie into wedges; serve with sliced berries.