We were so glad to have visited this place.
We were hesitant to visit as we didn't exactly know what to expect and there aren't a lot of information online about this place. But since it was pretty near our hotel, we decided to give it a shot and were very glad we did.
Kids Plaza Osaka is a indoor playground and science museum combined in one. There are lots to do for kids under 12 though I think the older kids will still have fun in some areas too.
On Level 5, there is a mock-up TV studio where you can pretend to be a newscaster and mucking around in front of the blue screen. There is also a science area and a little around-the-world area with different percussion instruments for the kids to play on. A mock-up train station is also available for kids to learn hot to buy their tickets to take the subway.
On Level 4, there is a mock-up supermarket where kids can shop and scan heir goods at the cashier. There is also a salon, a post office, a noodle stall where kids can play pretend. There is also an area for small kids to play the toys and train sets.
On Level 3 is the computer and craft area. We did not spend too much time here.
In the middle is a playground with a slide and some climbing structure which links up all 3 floors.
We spent a total of 5 hours here. My kids just couldn't get enough of this place :)

You can find something here for children of all ages from dressing up in costumes from around the world to standing inside a giant Bubble! With an area for Science and experiments, an area for role play activities like dressing up as a postman and walking around the "Little Town" and delivering the mail, and an amazing area for climbing and sliding and and running around, too many cool things to mention here. In general what every kid wants to do, all in a safe air conditioned environment, perfect for hot humid summer days of rainy winter ones. I can't remember the actual cost but I remember it was cheap I thought for the enjoyment that my two young children aged 4 and 5 got from it and the hours we spent there. and it's not too far from the train. There is a few vending machines there but there is a sitting area if you bring your own food and snacks, although it was very busy at the time). There is a MOS BURGER (Japanese style hamburger chain ) located right across the road from the entrance to the building. All in all I would recommend it to any parent looking for an fun day out for the children, even ones older than mine.