Abstract: The present invention concerns golf teaching apparatus in which a student swings a golf club over a target area having photocells. The outputs from the photocells are analyzed and displayed to give an indication of yardage and faults in the student's swing. In particular the photocells include two transverse arrays which are partially darkened by a passing golf club shadow so that the relationship between the number of photo devices darkened in the upstream array to those darkened in the downstream array is an indication of golf club direction. The invention is directed to concerning the error which arises if the two arrays are not located for maximum accuracy. Thus in accordance with the invention the two arrays are located symmetrically on either side of a line tangential to the target ball and at right angles to an ideal path of a golf club head when it impacts the target ball.