Background Since the introduction of the Swedish back school in 1969, back schools have frequently been used for treating people with low-back pain (LBP). However, the content of back schools has changed and appears to vary widely today. In this review we defined back school as a therapeutic programme given to groups of people, which includes both education and exercise. This is an update of a Cochrane review first published in 1999, and updated in 2004. For this review update, we split the review into two distinct reviews which separated acute from chronic LBP. Objectives To assess the effectiveness of back schools on pain and disability for people with acute or subacute non-specific LBP. We also examined the effect on work status and adverse events. Search methods We searched CENTRAL, MEDLINE, EMBASE, CINAHL, PsycINFO, PubMed and two clinical trials registers up to 4 August 2015. We also checked the reference lists of articles and contacted experts in the field of research on LBP. Selection criteria We included randomised controlled trials (RCTs) or quasi-RCTs that reported on back school for acute or subacute non-specific LBP. The primary outcomes were pain and disability. The secondary outcomes were work status and adverse events. Back school had to be compared with another treatment, a placebo (or sham or attention control) or no treatment. Data collection and analysis We used the 2009 updated method guidelines for this Cochrane review. Two review authors independently screened the references, assessed the quality of the trials and extracted the data. We set the threshold for low risk of bias, a priori, as six or more of 13 internal validity criteria and no serious flaws (e.g. large drop-out rate). We classified the quality of the evidence into one of four levels (high, moderate, low or very low) using the adapted Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. We contacted study authors for additional information. We collected adverse effects information from the trials. Main results The search update identified 273 new references, of which none fulfilled our inclusion criteria. We included four studies (643 participants) in this updated review, which were all included in the previous (2004) update. The quality of the evidence was very low for all outcomes. As data were too clinically heterogeneous to be pooled, we described individual trial results. The results indicate that there is very low quality evidence that back schools are no more effective than a placebo (or sham or attention control) or another treatment (physical therapies, myofascial therapy, joint manipulations, advice) on pain, disability, work status and adverse events at short-term, intermediate-term and long-term follow-up. There is very low quality evidence that shows a statistically significant difference between back schools and a placebo (or sham or attention control) for return to work at short-term follow-up in favour of back school. Very low quality evidence suggests that back school added to a back care programme is more effective than a back care programme alone for disability at short-term follow-up. Very low quality evidence also indicates that there is no difference in terms of adverse events between back school and myofascial therapy, joint manipulation and combined myofascial therapy and joint manipulation. Authors' conclusions It is uncertain if back schools are effective for acute and subacute non-specific LBP as there is only very low quality evidence available. While large well-conducted studies will likely provide more conclusive findings, back schools are not widely used interventions for acute and subacute LBP and further research into this area may not be a priority.