This hotel is pretty nice by Bangladesh standards. It is new, clean and popular with locals who use the restaurant often as it is the best place in town. The pool is massive but a bit deep. Even the baby pool is over 150 cm at its deepest. Sometimes the pool is very green, but if you ask them to pump out the water, they will do, so it will be nice and sparkling the next day. Ask when you book so it is ready. The pool is fenced and guarded, so bikini's are OK if you dare! They also have pedalo boats and a lake on the site where you can work up a sweat having pedalo races - not at midnight though!
Nearby:I would recommend Mastangha, Gokul Medh and Vishu Bihar. They are a bit busy (VB is quieter), but they are worth seeing as they supposedly are ruins of the oldest city in Bangladesh and only 15mins north of Bogra. If you walk far enough at Mastangha you can escape the crowds and potter around villages and play with goats etc... There is also a museum which is passable and has a few impressive statues and things in.
Bogra also has a Wonderland, similar to the Gulshan set up, so this is worth a trip for the kids also. If you like cricket, the stadium sometimes hosts international matches and these are fun to go to just to soak up the atmosphere, especially if Bangladesh actually look like winning. There is also a Rajbari in the centre - near Satmata which has some kids rides, but the museum inside the house is worth a look (Tk 2) at how the Raj's used to live a hundred years ago. A bit further away is the Jamuna river.
Take a trip for one hour (East) to Sarikandi where there is a ghat. You should be able to hire a country boat when you turn up for about Tk 500 and get on to the river and away from the crowds. You can even visit a char and have wander around. The isolation is a refreshing change from Bangladesh.