The places listed below are some of the most popular weekend getaways from bangalore, some of them are very near below 100km and some touch far, but belive me they are worth the travel, i can assure you, there is no way you are going to be disappointed, just go for it.

Balmuri Falls Near Mysore
Mekedatu, Sangama near Bangalore
Nagarhole National Park
Muthyala Maduvu Pearl Valley
Nandi Hills near Bangalore
Wonderla Amusement Park
Places Around Mysore
Coorg Kakkabe - Home Stay
Gopalswamy betta near Bandipur
Kemmanagundi

one of my best from above was the Coorg one, the homestay was a completely different experience and trekking in Kemmanagundi not to forget the falls near it.

When it comes to water games i dont think anything can beat wonderla atleast among the amusement parks we have now, mysore well i dont have say much about it.

Check this http://weekendgetawaysbangalor
e.blogspot.com

you will find all the information required.

Regards
Krishna
http://weekendgetawaysbangalore
.blogspot.com