I, too, schedule my boys at different times. One begins with TT first thing in the morning (first subject) on M/W/F and the other gets TT as first subject on T/Th/Sat. On the days they don’t do TT first they start with an independent reading and narration, so usually the timing works decently where they finish “subject 1” around the same time.
I will add that if you have multiple children on TT, having a second computer is very handy. For some this may sound like a luxury, but the nice thing about TT is that it can run on a fairly bare-bones computer and it doesn’t require internet access. That means an inexpensive, second-hand or refurbished computer will do the trick just fine! I have my third son coming up the line to begin TT next year so we’ve now loaded TT onto an old clunker laptap we got from a company going out of business. This computer is almost 10 years old, but TT works perfectly fine on it 🙂
Another point on the question above – when my kids do TT on the computer, they aren’t filling in the workbook at the same time, so the overall block of time spent in front of the computer is not usually longer than 15 minutes (20 minutes at the very most). My boys keep scratch paper or a lap size whiteboard beside them to do rough work when necessary, but for the other computer questions they can fly through pretty quickly just by entering the answer…makes the whole thing quite efficient! They do the workbook portion later in the morning or even after lunch (they choose). I like the fact that doing the workbook portion separately means that if they get stuck they have to look up and READ the math lecture notes that are at the front of each workbook chapter rather than always getting the help from the computer voice-over. In short, they are being taught their math both in audio/interactive format AND via book-reading. The combination of the two seems to be getting math to “stick” for us.
We have everyone use headphones, too.