So this is a project I wanted to engage in- To make a set of 10+ super-budget 60-card decks that are simple, relatively easy to play, relatively easy to understand, and bring across the fundamentals of how Magic Works.
The Idea being that you could easily build these deck for a low cost and use them as an easy introduction to how magic works, to teach a group of new players both how to play, and give them a sense of Why, a sense of what fun things they're getting into. These decks aren't gonna be particularly good, or even legal in any particular format if it stops me from including a card I think is good for the deck, but they should be fun and interesting without being too hard to get into.
This one I'm honestly not sure how well it came together, but I like it a lot regardless. There's an appeal to making a big attack with an Exert creature, fully prepared to untap it with Kiora's Follower afterward, and then when they try to block it and make a trade, you turn their creature into a frog and just stomp on it. And then when they try to crack back at you, You cast Triton Tactics and ruin their day. This deck is kinda sweet, and I feel like it's an easy one to get into because as soon as you wrap your head around "Oh, I turn it into a frog. Isn't that funny?" and "Okay, Exert makes sense", then you understand 90% of the weirdness the deck has to offer.
As for budget: Maindeck cost is currently at ~$9.25 (according to the middle blue numbers on this very site under estimated value), sideboard at about ~$4.80 because both of my card advantage spells are in standard at time of writing. If you want to replace them both with Curiosity and Sixth Sense, that'd probably cut the deck's price down by maybe a bit less than $2 total bit without loosing a ton of power. Up to you.
So mostly this section is going to be notes on why I think these are good cards to learn from:
The creatures are an interesting lot- Bitterblade, Stalwart and Naga are all Exert creatures, phoning in synergy with Kiora's Follower, as well as with Triton Tactics and Bounding Krasis if you use it to untap your creatures instead of taping theirs.
Bounding Krasis, by comparison, is mostly just a powerful creature with flash. The tapping is sweet, but mostly I just want a 3/3 flash.
Uninvited Geist is the only evasive creature in the deck, since the real goal is to pound through the enemy creatures with polymorphs and such, but after it connects once, it just deals great damage every turn.
Your polymorphs, Snakeform and Turn to Frog, are hilarious killspells in this deck, since so long as you can keep your opponents blocking your creatures, you can kill the creatures in the process. And if that fails, you have a playset of Nature's Way, so you can kill something precombat without taking damage on your creatures, and then slam in with Vigilance and Trample to make your attack step pretty nasty as well.
Triton Tactics is a hilarious blowout if you pull it off, letting you turn around an enemy attack to get some favorable blocks, and even if you don't kill their creatures, they end up staying tapped for quite awhile, so your opponent's shields are down. And if that opportunity doesn't show up, you can just use it to save two creatures in combat on offense, and that's still sweet.
Chart a Course and Curious Obsession are just good card-draw effects in an aggressive deck like this. You need to be attacking the whole time, so put that to use and make it benefit you.
Manabase is meant to be a touch lacking, but also super-budget. I'll be doing the same for all of them.
As for the sideboard, this IS supposed to be a sideboard they learn how to use, to make their deck perform better in the right matchups, or just in general to customize their decks within constraints.
Trygon Predator is tech against enchantments and artifacts, and is also just good if you want to ping in in the air every once in awhile. Extra copies of your card advantage spells lets you customize, and bring in extra value for some matchups, spell pierce is interaction, Plummet lets you take out fliers, and you have extra fight spells just in case.