If you want to add some extra culture to your vacation, put Osaka Prefectural Sayamaike Museum on your itinerary. Check if there are any guided tours or just roam around at your own pace.
When you've finished at this museum in Osakasayama, why not check out Aeon Mall Sakai Kitahanada, Big Bang, and Ario Otori? They're not far from Osaka Prefectural Sayamaike Museum and also popular with travelers.