I had some leftover worsted weight yarn in two colors so I made a striped child-sized hat:

(I used gray yarn as MC and pink yarn as CC.)

Using MC, cast on 76 sts using Long Tail Cast On.
Join to knit in the round.
Place marker to mark beginning of round.

Begin corrugated 2×2 rib pattern:
*k2 in MC, p2 in CC* around.
Work rib for 2.5 in.

Begin body:
Using MC, knit 8 rnds around.
Using CC, knit 8 rnds around.
Using MC, knit 8 rnds around.
Using CC, knit 2 rnds around.

Begin crown decreases (using CC for all rounds):
*k6, k2tog* until 4 sts remain, k4.
Knit 2 rnds around.
*k5, k2tog* until 4 sts remain, k4.
Knit 1 rnd around.
*k4, k2tog* until 4 sts remain, k4.
Knit 1 rnd around.
*k3, k2tog* until 4 sts remain, k4.
Knit 1 rnd around.
*k2, k2tog* around.
Knit 1 rnd around.
*k1, k2tog* around.
Knit 1 rnd around.
*k2tog* around.
*k2tog* around.
Break yarn, leaving 8 in of tail. Thread needle and run through remaining 5 sts.

Weave in ends.
Soak in Eucalan wash.
Block.
Wear!