Nina Spada is Professor Emerita of language education at the Modern Language Centre, Ontario Institute for Studies in Education (OISE), University of Toronto. Her work sits at the meeting point of second language acquisition research and the classroom, asking not whether grammar should be taught but when and how it best fits communicative teaching.
Spada is one of the central figures in the study of form-focused instruction, the practice of drawing learners' attention to language form inside otherwise meaning-focused, communicative teaching. With Patsy Lightbown she drew the influential distinction between isolated form-focused instruction, taught in a slot of its own, and integrated form-focused instruction, woven into communicative activity, and examined how teachers and learners weigh the two.
Her meta-analysis with Yasuyo Tomita (2010) synthesised classroom studies and found that explicit instruction produced large gains on both simple and complex grammatical features, and on measures of spontaneous production as well as controlled ones. The result is often read as evidence for the kind of practice-then-use logic that the 1990s critiques of PPP had dismissed, and so it figures in the modern reassessment of explicit teaching and the interface debate.
With Patsy Lightbown, Spada wrote How Languages Are Learned (Oxford University Press), a standard teacher-education text now in its fifth edition. The book is prized for translating first and second language acquisition research into terms a working teacher can use, pairing theory with classroom observation rather than handing down prescriptions. For many teachers it is the first bridge between SLA research and what they do on Monday morning.