A high consumption of discretionary foods and drinks has been associated with increased risk of multiple adverse health outcomes, including risk of overweight and dental caries. The family-based cluster randomized intervention study “Are you too sweet?” aimed at reducing the intake of discretionary foods and drinks in a population of children starting pre-school. As part of the intervention a new short web-based sugar-rich food screener (SRFS), was developed to make the parents and the school health nurses aware of the children’s intake of discretionary foods and drinks. In addition to the short assessment tool the parents also completed a validated web-based 7-day dietary record for the children. In the present study, estimates for intake of discretionary foods and drinks from the two assessment tools were compared (n = 80). There was significant correlation between estimates from the two assessment tools, but the SRFS provided lower estimates for intake of discretionary foods and drinks compared to the 7-day dietary record. The correlation coefficient between the two assessment tools was 0.49 (p < 0.001) and Kappa coefficient was 0.33. It is concluded that the SRFS can provide a fairly ranking of participants according to their intake of discretionary foods and drinks when compared to a validated 7-day dietary record. The screener may be a useful tool in practical settings, such as school health nurse consultations, in order to gain insight into the child’s sweet intake habits.