we aim to study from 9:00-3:00, but when life gets in the way the times change, but the order does not. If we need to shorten our day I either shorten the blocks to 30 minutes each or skip the after lunch subjects. My kids are older, but the same concept would work well with younger kids. For example, our day looks like this:
Dd: English, Languages (Latin & Spanish), Math, Science, Lunch, Geography, Literature, Flute Practice
Ds#1: Science, English / Latin, Math, French / Typing, Lunch, Geography, Literature, Drum Practice
Ds#2: Typing / Japanese, Math, English / Latin, Science, Lunch, Geography, Literature, Violin Practice
Mom: Spelling with dd (~15"), go over Science with Ds#1, English / Latin with Ds#1, English / Latin with Ds#2, Science with Ds#2, Lunch, chores / check e-mails / etc. but available for dc as needed, RAs with boys, chores / etc.
Ds#2 was 3yo when we began HS/ing. During lessons time he had a work list just like Ds#1 & did a lot independently. I had a basket with storytapes / book sets ( & a walkman), pattern blocks & cards, beads (with patterns on pipecleaners to copy on shoe laces), color or cutting pages, Spectrum preschool workbooks for phonics & math, etc. I would change the tapes, patterns, etc. weekly to keep the work fresh. Educational computer games are good for independent work with younger dc as well. My boys really liked the math blaster & reading blaster cd-roms.
Try something for a month, if it doesn't work try a different schedule. My HS is always a work-in-progress. Some seasons it's worked best to do all together work first, other seasons it's worked best to space out the together work.
JMHO,