A linear growth model was fit for the three measurement times over the 8-10 weeks that the teachers taught one science unit. The four outcomes measured were student scores on science vocabulary, science concepts, scientific drawing, and scientific communication at Times 1, 2, and 3. The models were fit on data from the 45 students identified by their classroom teachers. A linear model was fit for each of the four outcomes, based on inspection of scatterplots that failed to suggest a nonlinear model.

Science Vocabulary

The intercept or mean of the first point of measurement was 4.27 science words (see Table 1). The slope of 1.53 indicates that, on average, students acquired 1.53 science words between each interval of measurement. This means that, on average, elementary students increased their use of unit-specific science words by 1.53 words each time their writing was examined. Both coefficients for slope and intercept are significantly different from zero. Parameter variance associated with the slope was statistically significant, indicating variability among students in their growth trajectories. The standard error associated with the estimate for the variance is large, which is not surprising given the small sample size. The degree to which this variation in trajectories was explained by how much support a student needed (i.e., IEP, at risk, or typical) was explored. A model was fit, using "amount of support" as a predictor of the slope or growth trajectory. Results were not statistically significant (t = 0.28, p = .79); variance among individual student's growth trajectories remained high (7.42, p < .01). Thus, the predictor of amount of support did not explain the variation in growth trajectories. Consequently, on average, students with special needs and at-risk students increased their use of science vocabulary words in their writing at the same rate as their typical peers.

Scientific Communication

In Table 1, the intercept or mean of the first point of measurement was 2.40. This score was based on a 4-point rubric where a score of 1 indicated that the student's written response did not answer the question, there was no accurate detail, and no appropriate forms and conventions of science writing were used. A score of 4 indicated that a student's written response provided a thorough and complete answer to the questions, accurate detail was included, and appropriate forms and conventions of science writing were used. The slope of 0.23 indicates that, on average, students acquired 0.23 points on the rubric score between each interval of measurement. Both coefficients for slope and intercept are significantly different from zero. Parameter variance associated with the slope was statistically significant, indicating variability among students in their growth trajectories. A model was fit, using student "amount of support" as a predictor of the slope or growth trajectory. Results were not statistically significant (t = 1.46, p = .15). Thus, the predictor of amount of support needed did not explain the variation in growth trajectories. Again, we interpret this to mean that, on average, students with special needs and at-risk students increased the scientific communication in their writing at the same rate as their typical peers.

Science Concepts

In Table 1, the intercept or mean of the first point of measurement was 1.2 on the rubric. A score of 1 in science content indicated that the student's written response demonstrated an understanding of one of the science unit concepts and accurately uses little or none of the vocabulary specific to the unit. A score of 4 indicated that the written response demonstrated an understanding of the science unit concepts and accurately used science vocabulary words specific to the unit. The slope of 0.23 indicates that, on average, students acquired 0.23 points on the rubric score between each interval of measurement. Both coefficients are significantly different from zero. Parameter variance associated with the intercept and slope was not statistically significant, suggesting that, on average, individual students did not vary statistically in their growth trajectories. Consequently, we did not test to determine if there was variation due to the amount of support a student needed.

Scientific Drawing

In Table 1, the intercept or mean of the first point of measurement was 2.08 points on the rubric. A score of 1 on the rubric for drawing indicated that the student's drawing was not labeled or that the labels were incorrect, the drawing was more artistic than realistic, and it had no detail. A score of 4 on the rubric indicated that the drawing was completely and scientifically labeled, it is realistic, and it included relevant detail. The slope of 0.25 indicates that, on average, students acquired 0.25 points on the rubric score between each interval of measurement. Both coefficients are significantly different from zero. Parameter variance associated with the intercept and slope was not statistically significant, so we did not test to determine if there was variation due to the amount of support a student needed.

Thus, for each of the four outcomes there was overall student growth, regardless of the amount of support needed. It should be noted that while the findings on growth are based on a sample size with some statistical power due to the number of data points for each child (df = 134), the findings on the impact of amount of support are based on a small sample of children (df = 44). While the results are encouraging and generally positive, we acknowledge the need for caution in their interpretation. On another note, these changes, albeit small, were noted over the course of 8 -10 weeks when the teacher participated in the Action Reflection Process. This means that, if students increased the amount of scientific vocabulary used accurately in their writing by an average 1.53 words across each iteration, they learned and used an average of four words during this science unit, one of three science units they would be exposed to in a year.

To see what these changes look like on students' work, we include an example of the work of three students at three time periods (see Session 1, Session 2, and Session 3).