When you say clothes, do you mean a coat in winter, or the latest trendy sneakers and sparkly slogan teeshirt? i'd recomend making that one a bit more specific. Same with food -- there is a lot of variety, some you need, some you don't.
And fire -- most childrens' experience is only with a fireplace or campfire, which are purely for fun. If you mean heat for your house, or a heat source for cooking, say that. Brownies are very literal.
How do you think the group will define "need"? If you have a troublemaker kid like me in the group, she'll point out that human beings survived for millenia without clothes or school (though they're pretty necessary to be a normal person in today's western culture.)