Correction of exercises
Check that your pupils have played 3NT in South with the lead of Jack of Hearts. Remind them on this occasion that with two four card suits they should choose the one with a sequence.
play should go like this: the declarer lays a low card from dummy to try
to make his Queen (advice 23.1).
South takes with the Ace of Hearts, comes back to hand with the Ace of Spades, and must try the finesse on the King of Clubs, leading with the 10. This is the important moment of the deal: insist on the fact that East can duck once without cost … and that he cuts the communications of declarer, who will therefore only make two Club tricks (advice 23.2).
Don't get lost in the meanderings of the analysis of the end of the deal; merely indicate that South is limited to eight tricks (3 Spades, 2 Hearts, 1 Diamond and 2 Clubs).