Cut the tops off the strawberries, and slice them into a few pieces. In a medium bowl combine the sliced strawberries, sugar and vanilla extract and stir to combine well. Set aside and allow to sit, if you have time, for at least 20 minutes and up to 1 hour.
Place the strawberries with any juices, ice cream, and milk into a blender. Blend until smooth. Pour into large glasses, and if desired put a strawberry on the rim of each glass. Serve immediately.