If you liked the Mana Sorcerer manga, the Anime-Planet community thinks you'd like:
There's an adage that one man's trash is another man's treasure; but for Kosuke Ueki, one man's trash is another man's... tree?! Junior high school teacher Mr. K is in the running for the title of Celestial King. Candidates must select a junior high school student to endow powers upon, and then the students might fight each other mercilessly. The victorious student's benefactor will become the new Celestial King! Kosuke was Mr. K's choice, and for his power, he chose the ability to turn trash into trees. Furthermore, if he uses his abilities to harm others, he will lose one of his natural talents. Now, Kosuke must battle a variety of other power users to help Mr. K win it all, all while keeping his talents intact!
Although they're not overly similar, if you enjoyed Mana Sorcerer you might enjoy Law of Ueki based on the main characters' special abilities. Rouen is able to control mana, which manipules plant life, while Ueki can turn trash into trees. So if you enjoyed M.S. but it was a bit too short for you, try out Law of Ueki!