Yesterday we took our kids to Nielsen's grove park. It is on Sandhill Road out past the Wal-mart in Orem. It is one really cool park. There is a huge field area perfect for flying kites or launching rockets (that's what the boy scouts were doing.) They have a pond and a fountain. Plus a really nice garden of tulips.
The coolest thing is a merry-go-round-style set of swings. The swings go around in a big circle (I've seen similar things at amusement parks), but it is human powered. I wanted to swing on it so bad, but there were too many children wanting a turn. But sometime soon I'm going there in the morning so I can have fun.
There is also a playground, but it is small and for ages 5-12. I hope they are planning on adding a play area for smaller children because the smaller children play on that playset and get pushed over by older children.