Men are obligated to eat in the sukkah. Boys from the age when they can eat independent of their mothers (approximately 5-6 yrs old) are obligated to eat in the sukkah14. Foods that require a sukkah, may not be given to a child to eat out of the sukkah15. Women are not obligated to eat in a sukkah, but if they do so, they fulfill a mitzvah, and according to Ashkenazik tradition they may recite the blessing16.
14. Shulchan Aruch (O.C. 640:2)
15. Mishna Berurah 640:5
16. Shulchan Aruch (O.C. 589:6)