My two cents. So far, not much about what kids want. But, imho, almost everything else will be what the kids want.
Students then begin to set the modes, directions, etc. of investigation.
My job becomes providing tools, resources, frameworks to them as they explore. I've already constructed the measurement tool. When we complete the unit, students will show clear gains. This becomes a sense of momentum for the next unit. Okay, mebbe 2.5 cents.