Before they’ve uttered a single word, Maggie and playmate Zander, 15-month-old, are studying sign language. For the past three weeks, Ms. Searls and Zander’s mother, Vanessa Woolverton, have been making the drive from Killeen to sit with their children in a “Baby Sign” class offered by the Temple Cultural Activity Center.

The women say they hope signing will give the babies the ability to express themselves in the interim between crawling and speaking.

“I’ve learned a lot,” Ms. Searls said. But, she said, “Maggie hasn’t quite picked up anything yet. She can recognize (mom signs the word ‘it’), but she can’t do it yet”

Sign language classes for infants and toddlers are part of a national trend that has been introduced into classrooms and community centers across the U.S. and Europe.

The premise is that children understand words before they have the ability to pronounce them. Therefore, sign language gives the pre and post-“dada” set the ability to communicate.

On the morning of Aug. 15, instructor Brandi Kindred opens class like many other early child development classes with a “good morning song.”

Ms. Woolverton and Ms. Searls brightly sing along with Ms. Kindred, taking care to clearly pronounce each word while making its hand sign.

Next, it’s Ms. Kindred’s turn during a song that could be titled “What’s your name?” Ms. Kindred brings her hand to her temples in a pinching motion then with open palms and straight-outstretched fingers, lowers beside her face.

“Teacher,” she said indicating herself.

During much of the class, Zander and Maggie have the attention span of what could be expected of their age, but they clearly respond to the excitement. Maggie coos along with her mother and Zander flashes a smile.

“The more stimulus, the more they learn,” Ms. Kindred, who has a background in American Sign Language education, said after class. “If you incorporate music and movement and vocal sound, you get more immediate results.”

The hour-and-a-half lesson takes the occasional break for snacks and bubble-blowing time.

Only having attended six sessions of the class over three weeks, the two tots do not yet mimic their mothers’ and Ms. Kindred’s gestures but Ms. Woolverton said she sees improvement at home.

“One that he does a lot, when you say ‘what?’, he does this (Ms. Woolverton makes a shrugging motion).”

Classes like this were the topic of criticism when the phenomena became popular. Critics worried that pre-speaking children would become reliant on hand signs and therefore delay the motivation to attempt speech.

But apprehension about these classes has largely died down due to research, said Dr. Sherry Sellers Vinson, a developmental pediatrician at Baylor College of Medicine in Houston.

“There’s been quite a lot of research that shows that when you teach the word along with the sign that children actually start learning to speak earlier than predicted,” said Dr. Vinson, who also has a master’s in education. “And they actually start using the word without the sign.”

Dr. Vinson said that applying signs to the repetition of a word while signing creates a visual for the child to associate with the sound, which is more memorable.

“It’s a multi-sensory approach and most people learn better when they use more senses,” she said.

There’s another, less erudite, benefit to the use of sign language for children, Dr. Vinson said.

“The earlier that a child can express what he or she wants or how he or she feels, then the less tantrum-y,” Dr. Vinson said.

And that is one form of communication Ms. Searls said Maggie could do without.

“I just wanted to avoid the screaming,” she said.