Keep records on your students’ fundamentals. Do not proceed on to the next assignment until your student can perform the current activity with 80% accuracy. For example, when training with a table tennis robot, set it to a faster level of speed and/or oscillation if the student can perform 50% accuracy without footwork or stroke break down. Then continue the drill until the student can reach the 80% accuracy level. Then overload the student again by increasing the drill difficulty until the student reaches the 80% level. If the footwork, stroke breaks down or if success is below 50%, then you need to lower the difficulty.
By keeping records you can your keep your students advancing according to their ability.