AN: This is set pre-canon and is canon-compliant with Season 1 and Season 2 (so far), except for the fact that as per the Every End is a Beginning AU, Mac's dad left when he was 12 (which was what Jack said in one of the very early episodes of Season 1), not when he was 10 (which was what Bozer said in Flashlight and what they seem to have decided to run with). Honestly, 12 makes more sense, because Mr Ericson (Mac's 8th grade science teacher) noticed his grades were slipping when his dad left, and if Mac's dad left when he was 10, Mac was in the 8th grade at 10, and thus would have finished high school at 14, which meant he would have been 16 when he left MIT for the Army, which doesn't make much sense at all, unless, of course, Mr Ericson also taught Mac in earlier grades…anyway, exactly how old Mac was when his dad left really isn't all that important, so rant over.

No knowledge of the Every End is a Beginning AU is needed for this to make sense (except maybe the age bit above).

MR ERICSON'S CLASSROOM

MISSION CITY JUNIOR HIGH

MISSION CITY

CALIFORNIA

Mac swore under his breath as he heard footsteps coming down the corridor.

(He really wasn't supposed to be here. It was Christmas Eve, the school was closed, and he wasn't even a student here anymore; he was a freshman at Mission City High – at 12, the youngest freshman, which was…well, not fun; it'd have been unbearable if not for Bozer and Penny, in Mac's mind.)

(But even though he loved his grandfather, even though they were going to have Christmas dinner with Bozer's family this year – who were all excellent cooks – Mac hadn't wanted to be at home this morning, especially since Bozer was busy learning all of the details of his family's secret recipes and helping to prepare dinner, so couldn't keep him company.)

(So he'd snuck in – well, technically, broken in – to Mr Ericson's classroom, his favourite of all the labs in the building, because it was his favourite teacher's, and Mr Ericson still let him keep a couple of projects in the back room, to work on something to keep his hands and hopefully his brain busy.)

His beloved 8th grade science teacher stuck his head into the room, and he gave a wry little smile, shaking his head.

'Of course it's you, Mac, I don't know why I even considered it could be a burglar…'

Mac looked very sheepish.

'Sorry, Mr Ericson…'

Mr Ericson simply smiled, something long-suffering and exasperated and fond in his smile, in his eyes.

'Well, you're lucky it was me and not Coach Wilson.' Coach Wilson had something against Mac; he really hadn't been happy that Mac had made lightning in the Gym, even if it hadn't left any lasting damage. Mac nodded, again quite sheepishly, with a wry little smile. Mr Ericson gestured to the robot (or rather, robot-in-progress) that Mac had been working on. 'That your Science Fair project?'

Mac nodded rather proudly, as he started showing off the robot to his favourite teacher, explaining the plans he had.

'It's predominantly made of recycled DVD players, and I'm building a gyroscope system for the arm, for extra stability…'

Mr Ericson simply listened, fascinated, interjecting every now and then to offer a suggestion or praise or encouragement or a gentle warning to not test it out on the football field.

(He'd always been supportive of Mac, in all ways.)

(Did everything he could to challenge him intellectually in class. Encouraged Mac's 'extra-curricular activities', doing everything he could to gently divert them away from being destructive – accidentally; Mac never set out to cause trouble, it just tended to happen when he got too carried away. Entered Mac into the District Science Fair, and then the State one, and even a National one. Had noticed Mac's grades slipping, even if it was only very marginally, and worked out that there was something very wrong towards the end of 8th grade, when his dad had left.)

Mac left the school a few hours later to get ready for Christmas dinner, heading out the front door instead of through a window.

He turned and smiled at his 8th grade science teacher.

'Merry Christmas, Mr Ericson.'

Mr Ericson smiled right back.

'Merry Christmas, Mac.'

AN: I firmly believe that Mr Ericson was a very important influence in Mac's life, which is reflected in The Darkness Inside in Two Paperclips and a Stick of Gum.

Tomorrow's ficlet: 'You know, when I finally get around to making that movie I'm planning in which our titular hero MacGyver saves the world, with his team of course, I'm totally making you the endgame love interest.'

Now that's pretty obvious, methinks…and yes, that's kind-of a meta joke that just skims the fourth wall…