My kids are the same age and I am finding it tough, especially as this week the youngest started getting homework too. So now when I get home from work I have to do tea and consider homework and bathing them plus housework.
I already started the organised mum method for housework. 30 minutes a night dedicated to a room. I have a schedule on the fridge. I am also going to add to it which nights they do homework and wash so that we can get into a routine.
Example Monday is cleaning the living room and DS always gets homework so I will get him to do it on Monday so that I can potter around and be close by to help.
I also have a monthly meal plan so that I don't have to think too much about meals that they will both like. There is always at least one slow cooker meal and one/two night where the kids have omelettes or chicken and chips so that me and DH can eat something more adventurous.
My eldest has started getting pocket money in return for doing the dishwasher and setting the table at dinner which reduces workload ever so slightly.
I have started being much stricter with them when they make a mess. I simply don't have time to clean it up so they have to do it!
Don't beat yourself up. It's really hard work. Look for ways to make your life easier. Get your DH to help. I allocated my DH in charge of tidying the kitchen as it is the only mess he really sees. So I never do it because I know he will do that and I have other areas I need to spend time on.
I put a wash on in the morning and DH hangs it up later as he works from home.
I would love a cleaner but we can't stretch to it at the moment!