You can get your DS to list down the homework for the day and then do those that are supposed to hand in tomorrow (sometimes my DS teachers gave homework but to be handed in 2 or 3 days later). Once he finished, he can tick off the homework that was completed. By doing so, he can clearly see what he is supposed to finish and not be overwhelmed by the sheer load of it.
Time your DS. If it is compo, the child should finish within 50 mins and that is inclusive of planning the plot and writing it out. It is also training him to work within the exam time frame.
If he is still anxious, then i suggest that you seriously talk to your DS whether to drop the CCA to a non-competitve one (i presume his CCA is a competitve sports ?) The \"decision-making\" has to come from him so that he takes responsibility. If he likes his CCA and wants to continue it, then he really has to put an effort to focus at the NOW and just finish off the homework on hand.
my 2-cents worth of thoughts š
B