At home, he just started doing ALEKS and I'll probably print a bunch of their worksheets to send in for his homework. We have conferences in 4 weeks and I plan on talking to his teacher about letting him do ALEKS at least one day a week at school as well.
What we did, after discussion with DS's teacher, was to put a plastic folder in DS's school bag which, we make sure, always contains one ALEKS worksheet. His teacher takes it out when she wants him to do it, and when the folder comes home empty that evening, it's my cue to generate and print a new one. I think there are several good things about this system. The sheet he does at school is always recently generated, so its questions are the most relevant; his teacher knows there always is one there, but isn't under pressure to use it on any particular schedule (I trust his teacher's judgement: I suppose with a less trustworthy teacher, some pressure might be a good thing!); and even if DS doesn't talk about it I automatically know how much ALEKS he's doing at school!
Hope the talk goes well.