Study
Results

IMPLEMENTATION FIDELITY

Audio recordings indicated good implementation fidelity. All six target behaviors occurred regularly in the NPDT classes but only occasionally in the comparison classes. This suggests that NPDT was implemented as intended and that there was almost no contamination in the comparison condition.

EFFECTS OF NPDT ON STUDENTS’ FLE

The descriptive statistics for FLE at pretest and posttest are presented in Table 1. The linear mixed-effects model showed a significant Time × Condition interaction, estimate = 1.309, SE = 0.417, t(14.0) = 3.142, p = .007, 95% CI [0.415, 2.202], meaning that changes in FLE differed by condition. Follow-up comparisons of estimated marginal means further showed significant FLE increases in both conditions. The increase was larger in the NPDT condition, estimate = 2.005, SE = 0.394, t(7.0) = 5.090, p = .001, 95% CI [1.073, 2.937], than in the comparison condition, estimate = 0.696, SE = 0.135, t(7.0) = 5.141, p = .001, 95% CI [0.376, 1.017].

The fixed-effect estimates showed no significant between-condition difference in FLE at pretest and no significant effects of Grade or Teacher. The random-effects estimates indicated substantial correlation between pretest and posttest scores from the same student (ICC = .573), which was captured by the student-level random intercept. Overall, students in the NPDT condition showed significantly greater gains in FLE than those in the comparison condition.

ASSOCIATIONS BETWEEN NPDT BEHAVIORS AND MOMENT-TO-MOMENT FLE FLUCTUATIONS

Across the recordings, 562 NPDT events and 765 FLE-related vocal signals were identified. Nearly three quarters of these events (408, 72.6%) were accompanied by at least one signal, although the rate varied considerably across behaviors, from 49.3% for Affective Alignment (B2) to 89.1% for Youth-Culture Bridging (B5). As shown in Table 2, Exam-Strategy Instruction (B6) was the most frequently observed NPDT behavior and B5 the least frequent, while Student-Initiated Task Contribution (S3) was the most common vocal signal and Local Peer Affirmation (S4) the least common.

The model-adjusted estimates were similar to the raw co-occurrence rates. After accounting for Teacher and class-level clustering, B5 showed the highest probability of co-occurrence and B2 the lowest. Tukey-adjusted pairwise contrasts showed that B3, B4, B5, and B6 had significantly higher odds of co-occurrence than B2. No other pairwise contrasts reached significance. The model-estimated probabilities and significant pairwise comparisons are reported in Table 3.

Note. adj. p = Tukey-adjusted p value. Only contrasts with adj. p < .05 are shown. Each contrast compares the first behavior with the second.

STUDENTS’ EXPERIENCES OF NPDT BEHAVIORS

Semi-structured interview findings are organized around the six NPDT behaviors, aiming to trace how behaviors, feelings, and reasons were connected.

For B1 Co-Learning Stance, students felt that the equal-status relationship made classroom interaction less hierarchical and gave them a greater sense of emotional security and closeness to the near-peer teachers. Moreover, the step-by-step guidance further encouraged active engagement and confidence, while completing tasks together with the teachers gave students a sense of achievement. As P4 explained:

“I felt like we were more like friends [...] The teacher showed me what to do step by step, and then we did it together [...] I wanted to speak more in class, and I wasn’t afraid to ask when I didn’t understand something.”

For B2 Affective Alignment, students described a complex emotional response. Some felt surprised and embarrassed when teachers noticed their difficulties in front of classmates, partly because they had expected criticism. Once the teachers responded with affective support, however, these feelings often gave way to relief and gratitude, and students also felt closer to the teachers. When classmates also responded supportively, students tended to have a stronger sense of belonging in class. As P16 recalled:

“When the teacher noticed that I was not really following, I felt surprised and a little embarrassed because I thought she might criticize me […] But she just said it was OK and told us she had also struggled with this grammar point before [...] I was less afraid and decided to work harder, so I would not let her down.”

For B3 Dialogic Uptake, some students’ initial uncertainty was eased when teachers recognized their contributions and incorporated their ideas into subsequent classroom discussion. Such uptake made students feel valued and more confident, brought them closer to the teachers, and made the lesson more enjoyable and engaging. Recognition from classmates also gave students a stronger sense of pride and achievement. As P7 and P11 noted:

“The teacher kept saying that the next part came from my idea [...] My classmates also seemed to think my answer was valuable [...] I felt really happy and even kind of proud.” (P7)

“At first, I was not sure if my answer was right [...] but the teacher kept encouraging me and said we would continue from my answer [...] I felt really grateful, and I slowly became more confident and wanted to join in more.” (P11)

For B4 Strategic Teacher Self-Disclosure, students described two forms of teacher storytelling. Humorous anecdotes made the teachers seem less distant and the lesson more interesting and enjoyable. As P21 noted:

“The stories she told us were really fun, so I remembered them clearly [...] She did not feel like a strict teacher, but more like an older schoolmate who was close to us.”

Stories about past learning struggles revealed experiential similarity with students and illustrated possible ways of working through such difficulties, making students feel moved, inspired, and more confident about themselves. As P19 explained:

“When she talked about going to extra English classes in junior high school, I felt like she used to be just like us [...] It really touched me [...] I thought, if she could get through it and do well, maybe I could too [...] That made me feel more confident, and I really wanted to be like her one day.”

For B5 Youth-Culture Bridging, students felt that familiar youth-cultural references helped create common ground for interaction with teachers and classmates, which strengthened teacher-student closeness and classroom belonging. Moreover, seeing English as useful in everyday life further increased their interest and enjoyment and made them more willing to participate. As P2 and P9 noted:

“When the teacher started talking about slang from anime, everyone got excited [...] It was our first time talking about this in class, so everyone wanted to join in, and it was really fun.” (P2)

“Our teacher taught us many useful things […] I felt English was not only for exams, but something we could really use in life […] I kept imagining that I was talking with foreigners, it is very engaging.” (P9)

For B6 Exam-Strategy Instruction, students showed mostly positive, though sometimes mixed, feelings. They highly valued the exam-oriented strategies because of their practical use. Moreover, solving problems with these strategies also made them feel more confident and interested and gave them a sense of achievement. Some also expressed greater admiration for the teachers. However, when too many strategies were introduced at once, students could also feel pressured. Even so, they generally appreciated the teachers’ intention to help. As P14 and P23 noted:

“I really looked up to our teacher because her methods were actually useful [...] Sometimes there was just too much to remember at once, and I felt a bit stressed. But I knew she was only trying to help.” (P14)

“The exam tips were really useful [...] She also taught us some easier ways to remember words, like using phonics, a bit like pinyin [...] I’d never learned words that way before, and it actually made learning new words kind of fun.” (P23)

Overall, students’ experiences spanned all three dimensions of FLE—FLE-Private, FLE-Teacher, and FLE-Atmosphere—while also revealing some mixed feelings. These accounts add context to the audio findings and help interpret the variation in co-occurrence between NPDT behaviors and FLE-related vocal signals.