“They would rely on these families who age out of the game to then share their materials and give them advice,” said Shalini Shankar, a professor of anthropology at Northwestern University and the author of “Beeline: What Spelling Bees Reveal About Generation Z’s New Path to Success.”

“I think the scale of it got so big that at some point, they just decided to monetize it,” she continued.

Linda Tarrant, one of the nation’s foremost spelling coaches, said her company’s programs run at least eight weeks, with one hour of coaching each week by Skype or phone. But many students, she said, receive coaching for 18 months or longer.

“We teach vocabulary skills,” said Ms. Tarrant, who leads Hexco, a Texas-based company, and coached her three children in spelling. “We teach Latin and Greek elements. We teach rules for spelling words from different languages like Spanish and Japanese and Italian. The longer they’re in coaching, the more they get: They get down to Afrikaans, they get down to Polynesian.”

[We made a Spelling Bee quiz for you. Try your luck.]

Still, some people fear that the financial costs associated with spelling bees — travel expenses that can climb into the thousands of dollars and coaching bills that can run well into five figures — may be changing the character of the competitions. At the same time, experts said, youth competitions are changing in more arenas than spelling.

“I see it as keeping with what is happening with a lot of other aspects of children’s lives, and these kinds of pay-to-play competitions are so common in chess, in science fair,” said Dr. Shankar.

Last year, the Bee added a twist: Students who had lost at the regional levels would be allowed to compete in the national contest if they paid $750, plus expenses. This year, the “participation fee” doubled to $1,500, and the group of 562 included more contestants who had paid than those who had arrived the traditional way.