Hi daroo196. Good to be back again, after so many years absence.

Yes, it makes sense Frederick Collins drew it himself! Thanks for bringing that possibility to my attention! A man with such low self-esteem, who still holds on to his framed achievements of long ago, who’s always second best, having to answer to someone else at archery or the church choir, seldom taken seriously in his wishes and views, not even respected by his own wife and daughter, who defy him behind his back by continuing the relationship…

But on the 30th he was going to have a well-deserved break. He was about to expose a student of cheating big time. Then they would all finally see his worth. He was going to make especially sure this time, so he took his time to get his proof, time which may have been used to plan his murder…

Pet theory of mine:

Samantha Bragg’s wants to protect her son at all costs. She was feeding him test results at the cafetaria (where they never eat). She knows all will be revealed on the 30th October, where not only her son, but also she herself will probably be exposed. She organizes the sewing event on the 29th. She knows Fredrick goes by the clock, with a strict adherence to his protocol. She knows the minute when he will be outside after choir practice to get to his car. She had ample time to collect all the items from Marc, she needed. Thanks to his sloppiness, it wasn’t a problem.
She insinuates Marc had a huge row with Frederick before. She also insinuates the church secretary told her of an affair his wife was having, (who was most surprised at the idea at first)…

She locks the kitchen, where she had all the items she needed waiting for her, quickly disguises herself as Marc, (note she even observes how Marc would have tucked his hair under a hat to shoot better), climbs out of the kitchen, climbs up the tree, being a sporty, fit type with no problem whatsoever and makes the shot. She climbs down again and leaves the pin. First witnesses claim seeing a boy, (intoxicated) witness from the other side of the road claims to see a female running away. She discards weapon, hat, in the dumpster, etc., enters the kitchen again, unlocks the door and has a close encounter rushing into the lady with the incontinence, when a few minutes later the police arrive at the scene.

I’m sure there are still plenty of caveats…but at the moment, she is my prime suspect. (I still haven't got access to detective status, so am missing infos though)...Talk to you later...