The data in this deposit were collected as part of the <code>B@SEBALL</code> project (Biodiversity at School Environments - Benefits for All). The project investigated how biodiversity in the school environment can positively affect children’s health and mental well-being. <code>B@SEBALL</code> also investigated the opportunities for reducing health inequalities among children via biodiversity at school environments. The data are organized according to the Frictionless Data Package standard . All child-level and school-level data have been anonymized. Each data package is a collection of <code>csv</code> files and a <code>json</code> file. The <code>json</code> file holds descriptive information for all variables in all <code>csv</code> files. The <code>zip</code> file contains two frictionless data packages. The data packages contain information on 37 primary schools and 513 children. The data package, <code>data_package_an_zenodo_cleaned_data</code>, contains the original data in a tidied and cleaned format. It consists of 46 <code>csv</code> files. The files relate to the following contents: contents filename metadata file datapackage.json landscape level variables wp1_landscape_level_data.csv metadata about participants wp2_participants_metadata.csv general school level data wp2_school_data.csv pollution data at school level wp3_ua_sirm_data.csv classroom data about air quality wp3_ucl_classroom_airquality.csv area of ecotopes in the school environment wp3_ucl_ecotope_categories.csv greenness indicators for the school environment derived from ecotopes wp3_ucl_greenness_indicators.csv greenness indicators for the school environment derived from ecotopes wp3_ucl_greenness_key.csv greenness indicators for the school environment derived from ecotopes wp3_ucl_greenpatches.csv playground biodiversity indicators wp3_ucl_playground_biodiversity.csv d2-test of attention data wp4_d2_data_by_child.csv d2-test of ...