I think most golfers mistakenly try to get under the ball and lift it up in the air. This action causes the clubhead to reach its low point too soon and they lift up to compensate. Try and focus on letting the toe of the club turn down towards the ball and clip the grass in front. Understanding how the club is designed and used to make a divot can help a student comprehend the counterintuitive nature of hitting an iron off the grass. The leading edge of an iron must be lower at impact (slightly de-lofted) with a descending blow to make a divot. Pick a spot on the ground the size of a dime or smaller and brush the grass just forward of that. If you can do that consistently put a ball where the dime was and you love the result,