You might want to take his individual stroke times (for each stroke), and maybe time him when he does his IM. See how much he improves on each leg. Unspoken, his turns from stroke to stroke can make/break him, so those deserve practice minutes as well. In Summer Swim, have him sign up for each individual stroke, so he can judge his times dropping. And, since bribery works, we let our daughter pick where we went to dinner if she posted two personal bests in a meet. Needless to say, we had more than several Happy Meals, then she graduated to Home Town Buffets, and when she got to white table cloth dinners, she was in college. Great times, enjoy them, as they are oh so fleeting. PS, 200IM is a great event. When he gets older, stronger, more stamina, the 400IM might be his event.