Most people go to Laguna to take a break from the city. Swimming in one of the many private pools is a common activity. There are large public resorts but there are also a lot of private pools that you can rent.
For private pools, you can just go to Montevista Village, where 'manongs' on bike will guide you to any of the pools where you can make arrangements. It is helpful to tell them your budget upfront. In our case, it was P2500 per night. We got a place with two aircon rooms, one pool, area for cooking and meals, ref, and videoke (additional P500).