Add the strawberries, orange slices, orange juice, milk and sugar to the blender with 10-12 pieces of ice. If your blender is small, cut the strawberries in half first.
Pulse for 2-4 minutes, until the slushie is the consistency that you like. After two minutes, the ice will still be chunky, but for a creamy slushie, 3-4 minutes is best.
Pour into glasses and garnish with strawberries and orange wedges.