The White Dragon (original 1978; edition 1983)

THE LITTLE DRAGON THAT COULD

A ribbon of fire sliced through Jaxom's cheek, his right shoulder through the wherhide tunic, his forearm, his thigh. He felt, rather than heard, Ruth's bellow of pain.
   They came out of between above the little mountain lake. Ruth whimpering with the pain in his foot and leg. All he anted was to cool that Threadfire. Jaxom leaped from Ruth's neck and splashed water on his hide.
   That was better.
  We'll be much better at it next time," Ruth assured Jaxom. "I'm faster than any of the big dragons. I can turn on my tail and go between in a single length from the ground."
   Jaxom told Ruth fervently that he was without doubt the best, fastest, cleverest beast in all Pern. Ruth's green eyes whirled with pleasure. He was ready for any danger that might come.
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   Never had there been as close a bonding as the one that existed between the daring and adventurous young Lord Jaxom and his extraordinary white dragon, Ruth.
   Pure white and incredibly agile, Ruth was a dragon of many talents, though almost everyone on Pern thought he was a runt that would never amount to anything.
   But Jaxom knew better, knew he could teach his dragon to fly and to destroy thee deadly silver Threads that fell from the sky.
   Disobeying all the rules, Jaxom and Ruth trained in secret. their illicit flights seemed but a minor disobedience  until they found themselves in the path of danger and in a position to prevent the biggest disaster of all!

Third book in series

where a boy and his dragon

find their place in life.

(Rozax)