We have had some trouble coming up with a science curriculum that my son enjoys. If it were up to him, it would be science experiments every day. And while I know hands-on exploration is perfect for him, sometimes we need to just sit down and read and learn a few facts, too.
He is quite bored with his current curriculum. It's not bad; it's just that it is a little light on kinesthetic discovery. Instead, we have worked a new program into our curriculum that allows him a day out (for 2 1/2 hours) per week to meet with other kids his age and get his hands dirty.
He is taking the Junior Master Gardener class at our local zoo, Riverbanks Zoo and Botanical Garden. The program curriculum was developed by Texas A&M University through the help of some enthusiastic master gardeners who wanted gardening to come alive for the younger generation. If you don't see a class in your area, you can "grow" your own. The JMG web site provides details.
His Level One class is geared toward 3rd-5th graders, but there is a Level Two class for older students. If they complete all projects, they will receive a graduation certificate at the end of the semester.
I am not paid a dime by the JMG program, but I highly recommend it as a supplement for one semester of a homeschool science curriculum.