use minLength instead

it’s the same thing :). Thanks @rschamp!

src/components/forms/validations.jsx

@@ -12,9 +12,6 @@ module.exports.validations = {
     notEqualsField: function (values, value, field) {
         return value !== values[field];
     },
-    checkboxRequired: function (values, value) {
-        return value.length > 0;
-    },
     isPhone: function (values, value) {
         if (typeof value === 'undefined') return true;
         if (value && value.national_number === '+') return true;

src/components/registration/steps.jsx

@@ -534,10 +534,10 @@ module.exports = {
                                                options={this.getOrganizationOptions()}
                                                onChange={this.onChooseOrganization}
                                                validations={{
-                                                   checkboxRequired: true
+                                                   minLength: 1
                                                }}
                                                validationErrors={{
-                                                   checkboxRequired: formatMessage({
+                                                   minLength: formatMessage({
                                                        id: 'teacherRegistration.validationRequired'
                                                    })
                                                }}