Season 1 WGBH-TV , 2003 - 2004 Season 2 WGBH-TV , 2004 - 2005 Season 7 WGBH-TV , 2010 Season 8 WGBH-TV , 2010 Season 10 WGBH-TV , 2013 Season 12 WGBH-TV , 2014 - 2015 Season 13 WGBH-TV , 2015 - 2016 Season 14 WGBH-TV , 2016 - 2017 Watch now Season 15 WGBH-TV , 2017 - 2018 Watch now Season 16 WGBH-TV , 2018 - 2019 Watch now Season 17 WGBH-TV , 2019 - 2020 Watch now Season 18 WGBH-TV , 2021
, 2003 - 2004
