There is a small but interesting museum of Bedouin life that I think your children would enjoy and also the Dubai Mall which has a wonderful aquarium and is like a small city in itself(great for avoiding the heat). Jumeirah is good for the beach but I found it too hot to be even at the beach during the summer. For just a 24hr stay, a hotel closer to the airport might be more convenient and taxis are inexpensive.

The Gold Souk . . . even if you don't buy

Thanks for your replies
is the Dubai Mall the
Great Mall or the Emirates Mall - i heard there is a huge one with snow attraction inside too - what area is this Mall?

Great to hear about the taxis and can anyone recommend some local food - what area is best to venture out to taste local cuisine?

The Dubai Mall is the newest one; the Mall of the Emirates is the one with the indoor ski slope, and it's a great couple of hours entertainment for the family, even if you just ride up and down on the chairlift and drink hot chocolate in the snow! Very surreal. The MOE is on the Metro line and connected to the station by an air conditioned walkway.

The Madinet Zayed complex in Jumeirah is also nice; has an old souk feel, lots of lovely cafes and restaurants, and a view of the Burj Al Arab (the white sail shaped building).

The on and off bus is really a great way to see Dubai.You can decide whether you actually want to spend extensive time at a site or move on to another site. The bus tour includes a boat cruise across the river which is nice along with stops at the museum;Burg,the malls,the only mosque that Westerners can visit,etc.