We show results from b-learning strategy used to teach volume concept in high school for several geometric figure. We applied a conceptual volume test (pretest) and we found that high percentage of students had several misconception and low knowledge about prism and pyramids. We work with a control group (traditional) and, experimental group (b-learning); this methodology includes conceptual activities and use of Khan academy tool. Population was 50 students divided in two similar groups; distinction gender was no made. At the end of the course, we applied posttest; results indicate that Hake gain in experimental group (0.69) was larger than control group (0.45). In addition, hypothesis test for two sample indicate there are statistically differences between traditional and b-learning strategy which we can assume students in experimental group have better academic performance than students in control group (t=3.018>t_c=1.684).