This is one of the most inspirational, affordable, easy and space saving ideas I've seen. When it comes to the Montessori bathroom we often see parents use step stools for the children to access the basin or they provide a care of self-station with a low basin, perhaps a tub in a low table. Our bathroom is tiny and at 17 months I can't leave Otto's side when he is on the high step stool. He loves playing with water and will spend a lot of time brushing his teeth and washing his hands, I don't want to stop him or put barriers in his way. The basin on the bath is the perfect solution. He doesn't have to ask to use it and it requires minimal supervision.
It's safe, Otto can't fall. It's space saving, it fits on the edge of the bath it doesn't take up any floor space. It's affordable, ours was around £17, it's made in Germany and I was so surprised to find the plastic is quality and it is recyclable. It's super easy for the child to use. It works!
Before it was mentioned on the Montessori Family UK Facebook page, I don't recall seeing this type of children's basin before, it's worth joining Montessori Facebook groups, especially those that are local to you, you don't know what you'll discover.
I went searching to see if anyone else had used the basin on the bath and found this fantastic set up at Midwest Montessori. In the UK we use the Babydesign Kiddy Wash (here in France, also at Oxybul) (BTW the mirror is a sticker and it isn't the best mirror image). There are a couple of alternatives in the US, Amy from Midwest Montessori notes they use this one (although no longer available). The basin on the bath really needs to find it's way into Montessori stores!! It promotes independence in such a family friendly way.