R.S.
Are your Monday mornings rushed and very different from Sat and Sundays? Does he wake up at drastically different times on the weekend? Do you let him know Sunday he is going to school and you and/or your husband are going to work on Monday? is he throwing more temper tantrums lately in general, maybe it is getting him extra attention.
Maybe make a photo calender of the week, for school days put a photo of him going to school and you going to work and for Sat/Sun/Holidays put up a photo of all of you at the park or something. Then let him help you set it up every Sunday evening. That way he will know what to expect and he can anticipate the week. I have to constantly tell my kids our schedule, sometimes hour by hour to keep them feeling like they have some control.
Hang in there,
R.