Done and done! All I needed to buy was some good medium-weight fusible interfacing, since we already had scads of sparkly fabric lying about around here. (Those remnant bins at the fabric store? They're like heroin.) And thanks to coaching my teenage babysitter on SAT math over the last few weeks, figuring out the pattern for the conical hat was pretty simple:

1. Measure child's head,

*c*

2. Determine height of hat,

*h*

3. Calculate the diameter,

*d*, of a circle with radius

*h*.

4. Set up an equation:

*c*/

*d*=

*a*/360. Cross-multiply, solve for

*a*.

5. Draw a wide wedge of pie with interior angle

*a*and radius

*h*. This is your basic pattern piece to make into the hat. Cut one of these in interfacing, then add seam allowances around all sides and cut this piece in fabric. Cut a rectangular piece of sheer fabric with length

*h*and width about 2

*h*.

6. Hem, iron, sew two seams. I think the whole process took about half an hour, and we ended up with this:

(Oh, wow, I'm

*such*a nerd. Does Omnigrid make a slide rule?)