Topiramate (marketed under the brand name Topamax) is approved by the U.S. FDA for the prevention of migraine headaches in adults. The FDA has also approved topiramate for epilepsy (a seizure disorder) and for use as adjunctive therapy (meaning in combination with other medicines) for partial onset seizures in adults. Topiramate is not approved by the FDA for use in adults or for use in children and adolescents who have bipolar disorder. This study is being done to see if topiramate, in combination with quetiapine, will reduce bipolar mania and reduce cannabis use.