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Mary Pope Osborne's Summer of the Sea Serpent is a proper quest for 7 year olds, with a rhyme to follow and a sword to find before dark.
It is the longest day of the year in Frog Creek. A seagull turns up two hours from the sea, screeching, and Jack and Annie know exactly what that means.
The magic tree house is back.
Inside there is a pale blue shell with Merlin's handwriting on it. On the other side is a poem. A shining sword has to be in their hands before night falls, or Camelot's king is done for.
The poem is also the instructions. Call the Water Knight. Get through the Cave of the Spider Queen. Swim with a selkie. Dive under something called the Cloak of the Old Gray Ghost. Answer a question with love instead of fear.
Annie says straight away that she is worried about the spider part. Jack says he is worried about the ghost part. That is a nice touch. They read the list, they say out loud which bit frightens them, and they go anyway.
Then the tree house lands. No village, no people, just a gnarled tree on a sea cliff under snowy mountains and three coves below with caves in the rock. Annie calls it wild and lonely and she is right.
This is a later trip for Merlin rather than one of Morgan's, and the tree house has been gone a while, so the two of them are out of practice and know it.
Reading it feels a bit like being handed a treasure map. Every few chapters another line of the rhyme comes true. Your reader will be ahead of Jack, working out what a selkie is likely to be and dreading the cave.
Two things to look at before you hand it over. The Cave of the Spider Queen is exactly what it sounds like, and it is announced in the rhyme on the very first page. There is also a lot of deep water and diving. A child who is happy with witches and knights may still find a spider queen a bit much, so it is worth a flick through first.
If they are fine with all that, it is one of the more exciting ones. Sea, cliffs, a talking creature or two and a ticking clock.
The invitation that took Jack and Annie to Camelot one Christmas Eve is still lying in the tree house at the start of this book. That trip is Christmas in Camelot and it is in the library too.








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