The star is pretty easy. I've made several for our Christmas Tree and I've used it as a starfish before too.
Start with a sliding loop
15 sc in loop
join with slip stitch first sc
each point is worked and then rejoined to the circle just made before the next point is started
sc in 2nd chain from hook
half double crochet
skip two stitches on circle and slip stitch in 3rd stitch.
Do this 4 more times and you'll have a 5 pointed star. Each point uses 3 of the stitches on the circle, so you could easily increase it to 6 points or more by just increasing the number of sc you start with.