Try Splat

var canvas = document.getElementById("canvas");
var manifest = {
	"images": {},
	"sounds": {},
	"fonts": {},
	"animations": {}
};

var game = new Splat.Game(canvas, manifest);

game.scenes.add("title", new Splat.Scene(canvas, function() {
	// initialize the scene

this.player = new Splat.Entity(100, 100, 30, 30);
	this.player.draw = function(context) {
		context.fillStyle = "#ff0000";
		context.fillRect(this.x, this.y, this.width, this.height);
	};

this.floor = new Splat.Entity(0, 220, canvas.width, 20);
	this.floor.draw = function(context) {
		context.fillStyle = "#0000ff";
		context.fillRect(this.x, this.y, this.width, this.height);
	};
}, function(elapsedMillis) {
	// update the simulation / call .move() on everything

this.player.vx *= 0.9; // friction
	this.player.vy += 0.01; // gravity

if (game.keyboard.isPressed("left")) {
		this.player.vx = -0.3;
	}
	if (game.keyboard.isPressed("right")) {
		this.player.vx = 0.3;
	}

this.player.move(elapsedMillis);

if (this.player.collides(this.floor)) {
		this.player.resolveCollisionWith(this.floor);
		if (game.keyboard.isPressed("up")) {
			this.player.vy = -0.3;
		}
	}
}, function(context) {
	// draw the frame / call .draw() on everything

context.fillStyle = "#000000";
	context.fillRect(0, 0, canvas.width, canvas.height);

this.floor.draw(context);
	this.player.draw(context);
}));

game.scenes.switchTo("loading");