On the call side, KB Home (NYSE:KBH) calls are trading over 10 times their average volume follow this morning’s Case-Shiller report. Hansen Natural Corporation (NYSE:HANS) calls are trading over 6.5 times their average volume after one investor purchased a large block of calls on the beverage manufacturer. EnCana (NYSE:ECA) calls are not far behind, trading at just under 6.5 times their normal volume. Mylan (NYSE:MYL) calls are trading at around 5 times their average amount after Citigroup analysts upgraded the stock yesterday. Finally, MannKind (NASDAQ:MNKD) calls close out the list at 4.7 times their normal volume after the company released positive news about their diabetes drug, AFREZZA.Taking a look at the put side of the ledger, Popular (NASDAQ:BPOP) puts are currently trading at over 24 times their average volume after several investors placed bearish bets on the company. Western Digital (NYSE:WDC) puts are very active today, trading at close to 11 times their average volume. Barnes & Noble (NYSE:BKS) puts are trading at 6.5 times their average volume following news that takeover bids for the company may have dried up. PulteGroup (NYSE:PHM) puts are not far behind, trading at 6.2 times their average amount. Finally, Ariad Pharmaceuticals (NASDAQ:ARIA) puts close out the list at just under 6 times their average amount.