Hi Susan,
I perfectly understand your concern as I am a mum too and I run several airbnbs, one of which is a room in my house. At the really beginning, more then 2 years ago, I did start giving the guests strict rules on house access, but it wasn't easy and it wasn't working. The first impact is that you don't trust your guests, so they will not like / trust you and the whole airbnb concept it really melts down. You can't really say to a guest , perhaps on holiday the most of the time, to get out of bed at a precise time and get out of the house at a set time during their stay. On the first day indeed you set the time for check in etc... but then during the stay it is different. A set time everymorning to go out sounds quite awkward and not really polite. My advice is to take the matter in a different prospective and accept booking from females only for example, if you feel better (it is just an example).
Anyway if you explain it VERY well in the house rules and description in ADVANCE you are free to set whichever rule you want, and you will get booking anyway but in few weeks/months you will realize that reviews aren't great and guests they will moan about this, hence your bookings will start to decline, so in the long term would not be beneficial. You really need to understand that people using Airbnb are jsut like you and me, they respect family values etc... before being able to book anyone need to upload all the documents etc... I think it is a very safe enviroment.
I always say to people wanting to do Airbnb in their property to think from the guests prospective. Do you like if you book a place for holiday and the host says that you have to go out at 8:30 am? and then you can't access the property all day? And you don't trust them to have the key? By Law you can't restrict the access to their properties (documents, medications) in the room .... what if they need to leave and they need to get their gear/mediacation?
If you really don't bother the only way to get around this in a nice way is to set the booking as 1 day maximum , in this case you will only have guest staying 1 night hence don't need to give the key etc.... but as you may understand you won't have many booking (depending on where you are based ... airport location gets 1 day booking request as they are used as a stop over before early flights etc...)
I hope my comment helped, don't hesitate to ask if you need any advice.
Cheers
Paola