Monitor Lizards belong to the family Varanidae, which is monotypic or having only one genus, called Varanus.The name Monitor Lizard refers to the tendency of these reptiles to extend their long necks and stand on their hind legs as if to “monitor” their surroundings. Most species are large, like the 9-foot Water Monitor, although some can be as small as a few inches in length. Most are also fiercely aggressive, while others are shy and withdrawn. Monitors are robust animals with well-developed limbs, powerful lashing tails, strong jaws, long necks, and sharp claws. When threatened or expressing hostility, they spread their ribs, flattening the top of the body and expanding the belly to make them look large and ominous. They open their mouths and hiss, rise on their hind legs, and whip their tails to attack.
This species also can be found in our school, very lucky myself because have a snapshot of it two years ago. Just for a look for it, here it is :