It's the Easter Beagle, Charlie Brown, on CBS
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This is the twelfth "Peanuts" special, which first aired in 1974 (the year before I was born). I suppose I must have seen a rerun sometime when I was a kid, in the 80s, but I've never really remembered anything other than the title. I finally watched a rerun again on Easter of 2013. It wasn't bad... a few parts were reasonably amusing (like how the department store the kids go to at one point had Christmas stuff on sale, about nine months early). But basically I just found it sort of innocuous... a sort of pale retread of It's the Great Pumpkin, Charlie Brown, which in fact Sally references when Linus talks about the "Easter Beagle" showing up on Easter morning to pass out eggs to children. (Spoiler alert: unlike the Great Pumpkin, the Easter Beagle actually does show up in the end. Sort of.)
Anyway... there are various plot threads going on, including Snoopy buying a birdhouse for Woodstock, who was upset about getting rained on. And Peppermint Patty trying to teach Marcie to color Easter eggs, except Marcie finds every conceivable way to cook the eggs wrong. And, um... I don't know what else to say. It's no wonder I didn't remember the plot from my childhood, considering that as I type this, I just finished watching it half an hour ago, and already my memory of it is fading. Oh, but apparently (according to Wikipedia), some scenes have been cut from the original special. That's a shame, I'd like to see the whole thing, sometime. Maybe someday I'll get a DVD collection of specials.