On the last Monday of my 2014- 2015 academic year, I went on a field trip with all of my Grade 8 students to the botanical gardens in Bogor.
There are a lot of beautiful plants and lilly ponds, but mostly it was nice to get out of Jakarta with my students. Not only did we get to breathe in some fresh air, but I also got to experience my students in an enviornment that is not my classroom. (That pretty much just meant that I got to hear them whine about how hot it was outside and pick up their phonecalls when they got lost in the massive garden, but the change of pace is always welcome!)
If you are looking for an escape from Jakarta, this is a perfect place for fresh(er) aire, a nice picnic, or a photo shoot! There are lots of shady spots and you can rent a bike for 15000RP or get a tour in a open air vehicle for 10000RP. Because the altitude is higher, the temperature is a bit lower, too!