Stay at home moms in school

How do you do it? I have a 3 month old who is up all day. I'm only ever able to get homework started after my husband gets home at 7 and I go to bed at 10. My son wakes up at 11:30, 4:30 and we are up at 7am. I really need help. During the time my husband is home he takes 3 naps the first is always 30 minutes, the second might be 30 minutes to an hour and the last nap is usually during the time I'm picking my kids up from school and it's the longest nap because he falls asleep when I put him in the car seat and doesn't wake up until we get home. During the day he needs so much attention. I have been thinking about getting a baby carrier and seeing if I can hold him in that so I can get more time to get my homework done. Does any one else have any tips that is working or worked for them. I just need more time to do homework and I don't want to fall behind.