Children’s BMI Tool for Schools

The BMI Tool for Schools is being updated to match the Child and Teen BMI Calculator. For the most accurate BMI percentile calculations, please use the individual Child and Teen BMI Calculator at this time.

The Children’s BMI Tool for Schools is an Excel spreadsheet intended for use by a school, child care, and other professionals who want to compute Body Mass Index (BMI)-for-age for a group of up to 2,000 children (metric version) or 20,000 children (U.S. version).

This calculator computes BMI and BMI percentiles for individual children in a group using height and weight measurements, sex, date of birth, and date of measurement information that you enter, or import from a spreadsheet or data file. It provides a group summary of children’s BMI-for-age categories and graphs for Prevalence of Overweight and Obesity, and Prevalence of Overweight and Obesity by Sex.

This calculator is an Excel spreadsheet that can be downloaded onto your computer. To allow all of the features of this calculator to work, please click “Enable Macros” if prompted when you open the application. The spreadsheet has 3 worksheets entitled “INSTRUCTIONS”, “MEASUREMENTS”, and “GROUP SUMMARY”. You can view each of these using the tabs at the bottom of the window.

Body Mass Index Measurements in Schools

This resource describes the purpose of school-based BMI surveillance and screening, examines current practices, summarizes the recommendations of experts, identifies concerns surrounding programs, and outlines needs for future research. Guidance is provided on specific safeguards that need to be addressed before schools decide to collect BMI information.

BMI Measurement Program Safeguards

Following is a list of safeguards that schools can use to address concerns that have been raised about school-based BMI measurement programs and increase the potential positive impact the program may have on promoting a healthy weight.

Safeguard 1. Introduce the program to parents, guardians, students, and school staff; ensure that there is an appropriate process in place for obtaining parental consent for measuring students’ height and weight.

Safeguard 2. Ensure that staff members who measure height and weight have the appropriate expertise and training to obtain accurate and reliable results and minimize the potential for stigmatization.

Safeguard 3. Ensure that the setting for data collection is private.

Safeguard 4. Use equipment that can accurately and reliably measure height and weight.

Safeguard 5. Ensure that the BMI number is calculated and interpreted correctly.

Safeguard 6. Develop efficient data collection procedures.

Safeguard 7. Do not use the actual BMI-for-age percentiles of the students as a basis for evaluating student or teacher performance (e.g., in physical education or health education class).

Safeguard 8. Evaluate the BMI measurement program by assessing the process, intended outcomes, and unintended consequences of the program.

Additional Safeguards for BMI Screening Programs

Safeguard 9. Ensure that resources are available for safe and effective follow-up.

Safeguard 10. Provide all parents with a clear and respectful explanation of the BMI results and a list of appropriate follow-up actions.

Source: Nihiser AJ, Lee SM, Wechsler H, McKenna M, Odom E, Reinold C, Thompson D, Grummer-Strawn L. Body Mass Index Measurement in Schools. Journal of School Health. 2007; 77:651-671.

For more information about school-based BMI surveillance and screening refer to: Body Mass Index Measurements in Schools

Connect with Nutrition, Physical Activity, and Obesity