We all know the first line of a query is your "hook." I call the last line the "sinker." You want it to punch them in the face, in a nice, friendly kind of way that makes them unable to forget you after having read the 300 other queries in their inbox.
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Everyone else thinks Dad had a seizure, but he isn’t waking up and the doctors are talking about surgery. My fact-based is already saying "coma" instead of "isn't waking up" and wants to know what kind of surgery could possibly be helpful, but this is MG, and since a 12 y/o wouldn't think this way, it might be OK, I do think the sentence can be cut after "isn't waking up" though. The rest is not relevant to the query. Grandpa wants to take Juniper to the hospital to say goodbye just in case, only once he gets her in the car for flow I'd change this to something more like, "on the busy highway", he misses the exit. Instead they travel to Agartha, the city at the center of Earth, and home of the blasted toads. Grandpa is sure they can find a cure. Why would he think this? And also, it makes me wonder if he took this side trip on purpose?
When they get there, Juniper isn’t sure of anything. Grandpa is infamous Ah, so he's been there? Need to extrapolate, the city of Agartha is dying, and the natives want her to save it. Oh and apparently she’s got powers: she can bend the air, manipulate any living plant, and heal minor injuries. This is weird, but cool, and also useless because she doesn’t know how to summon any of them.
The natives want her to travel to a pond with waters that can heal anything comma including Dad’s poison. Technically it's healing Dad, not his poison. Of course the pond is far away, surrounded by savage animals, and cave-ins are happening all the time. Cave-ins? Is it underground? The natives also reveal that Grandpa is responsible for the destruction of Agartha and ultimately Earth. That's a leap -- like Agartha holds up Earth, or Earth's survival is dependent upon Agartha's? Grandpa assures her he had good intentions. Whatever. Now she has to clean up his mess, except her powers are wonky at best, she doesn’t know who to trust, and when she requests soldiers for help, they send her one inexperienced teenage boy. Older than her? Also an Earthling? They might as well be asking her to steal the moon.
FOLLOW THE YELLOW SICK TOAD is a middle grade fantasy novel complete at 50,000 words.
Thank you for your time and consideration.
This is definitely cute and sounds like fun, but I think you need to explain a little more about how Grandpa is responsible for the destruction, and why Juniper would have powers. Also, the title makes me think this is a play on The Wizard of Oz somehow, but I'm not seeing that in the query. Overall I think the idea could definitely work, but the query needs some clarity - you're close!