https://muted.io A more advanced music theory explanation sight, with a few basic games, but many embedded apps as well.

https://www.musictechteacher.com/music_quizzes/music_quizzes.htm A ton of cool games!

https://classic.musictheory.net/brass/ – Brass fingering and slide position game! Just make sure to SELECT “YOUR” INSTRUMENT under SETTINGS.

http://musicracer.com/  Learn your NOTES. Learn your FINGERINGS (all wind instruments). Learn your MUSICAL TERMS! Competitive and Non-Competitive options!

https://www.musictheory.net/  –Note naming drills. Choose your clef, choose your range.  All under Settings.