The Midland Wachusett League (Mid-Wach) is a high school athletic conference located in District 3 of the Massachusetts Interscholastic Athletic Association. The Mid-Wach was formed in 1989 as a merger between the Midland and Wachusett leagues. The league consists of twenty-seven public high schools in the Worcester County and Middlesex County of Massachusetts.
The league is separated into four divisions (A, B, C, and D) by size of school. Shrewsbury High School is currently the largest with 1,879 students, while Murdock High School is the smallest with 252 students.
The Mid-Wach sponsors eighteen different sports across all divisions in the MIAA, and is the main league in central Massachusetts.
The Midland and Wachusett leagues were two of the oldest leagues in the state, but as both had been growing over the same area over the better half of the century, they decided to merge in 1989. Three years later in 1992, Westford Academy who had been in the Wachusett League for many years left for the Dual County League for more recognition and a chance to fit in better with the other schools. In 1995 Murdock High School joined bringing the number of schools in the Mid-Wach back to twenty-two members. A year later, The Mid-Wach admitted Bromfield, Tahanto, and West Boylston all from the Dual Valley League, which brought the total membership up to an even twenty-five. It wasn't until 2011 where the league changed again, this time admitting Tyngsborough from the Dual County, who was outclassed in most sports in the DCL. A year later, longtime member Milford elected to leave for the Hockomock League, citing travel expenses as one of the main reasons for the move. In 2013, Shepherd Hill joined looking for better competition than what they had in the Southern Worcester County League. After also outgrowing the SWCL, Grafton High School joined the Mid-Wach in 2025 as part of the A division.
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This is a list of MIAA State championships won by schools while a part of the Mid-Wach league
Note: From 1972 to 2012, football state championships were separated by region, so there would be multiple champions from each division. From 1972 to 1977 and from 1997 to 2008, it was split between Eastern Mass and Central/Western Mass and there would be two champions in each division. From 1978 to 1996 and from 2009 to 2012 Central and Western Mass split so there would be three champions in each division. In 2013 everything was combined and therefore only allowed one state champion per division.
Algonquin - 1994, 2011, 2012
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