Collaborative dialogue is rich in conscious and subconscious coordination behaviours between participants. This work explores collaborative learner dialogue through theories of alignment, analysing inter-partner movement and language use with respect to our hypotheses: that they interrelate, and that they form predictors of collaboration quality and learning. In keeping with theories of alignment, we find that linguistic alignment and gestural synchrony both correlate significantly with one another in dialogue. We also find strong individual correlations of these metrics with collaboration quality. We find that linguistic and gestural alignment also correlate with learning. Through regression analysis, we find that although interconnected, these measures in combination are significant predictors of collaborative problem solving success. We contribute additional evidence to support the theory that alignment takes place across multiple levels of communication, and provide a methodological approach for analysing inter-speaker dynamics in a multimodal task based setting. Our work has implications for the teaching community, our measures can help identify poorly performing groups, lending itself to informing the design of
real time intervention strategies or formative assessment for collaborative learning.