Although schools' rugby was still strong in the 1970's the various national unions believed that youngsters should be introduced to the game at primary school age. This took the form of mini rugby enthusiastically embraced by Kirkcaldy from 1975 onwards. Midi rugby for boys up to sixteen years followed two years later. Kirkcaldy formed their first colts' team, originally aimed at boys who had already left school at sixteen but this target was never attained. By the end of this decade Kirkcaldy had a full range of youth teams from Primary Four up to Under 18, all well supported and enjoying success.

The Colts side won the first ever SRU National Youth League final in 1981 beating Melrose in the final at Murrayfield and retained the trophy the next year. Captains of these sides, Alex Carruthers and Andy Henderson, both went on to serve the club well in the years to follow, each serving as captain and first team coach with the latter holding the record for most 1stXV league played in the club's history until 2014.

For the senior side life in the third division was anything but easy, with frequent brushes with relegation. However as the first products of the original colts teams matured a particularly strong side emerged, coached by Terry Trewartha, which won the third division title with a 100% record. Trewartha, who had four separate spells as first team coach, was associated with the side from the National League Division Four in 1973 to Premiership Division One in 2000 when he finally retired.