re: Yellowstone or yosomite for a springtime family trip?

I worked in Yellowstone while in college, and remember arriving in mid May & there was still snow on the ground in some places. But not enough to cause any real problems. Just check the forecast when making any reservations earlier in the year. The main advantage in going in the Spring is that it is not crowded..late June through mid August the park becomes a parking lot at times. And lines everywhere. But wherever you end up, when you get there, talk to some of the student employees & ask them where they go on their off days, as they know all the best spots, i.e. for viewing & tourist avoiding. For instance, 99% of the tourists watch Old Faithful go off from the main viewing areas. There is a hiking trail up a nearby mountain, ending up in a shaded area, several benches, that gives a great view of Old Faithful & odds are no one else will be there.Down below, usually there are hundreds packed in next to each other.