Are there any specific strategies in Jenga?
The most unstable situation is adjacent middle blocks, and in general, instabilities near the bottom of the stack are more likely to cause the tower to fall than those at the top because of the greater weight of blocks being held up by the rickety base and because of the longer moment arm. 



However, it's not quite as simple as setting up a precarious-middle-blocks-at-the-bottom-of-the-tower scenario just to make your opponent move after you've set it up, as the picture makes clear that several middle blocks in a row can often be stable enough for at least a couple more turns--in which case your ploy could come back to bite you. 

One trick I've used is to judge which way the tower was tilting after I'd removed my block and then place it on the opposite side on the top. The goal here is to make your opponent place their block on the weak side and hopefully bring everything down. It has the added benefit of being the safest place to put your block.

That said, there's not much strategy to Jenga; it's really more about steady hands, dexterity, and being able to tell which blocks are loose. (Unless of course you engage in psychological warfare.)