Nature Study Lesson 174: Maples
The small three-lobed (red) leaf is a Black Maple. This tree is similar to sugar maple but usually 3-lobed (sometimes five); often appears to be drooping; often with a thicker leaf and leaf stem (petiole) than sugar maple, usually with two winglike or leaf-like growths at the base of the petiole (stipules). "The sugar maple grows very rapidly, and is therefore a useful shade tree. Its wood is used for many purposes, and from its sap is made a delicious sugar." -Handbook of Nature Study, page 632
The green leaf with a purplish tint is a Red Maple. It's tree has 3-lobed or weakly 5-lobed leaves 2-6 inches wide which have sharply V-shaped sinuses and small sharp teeth along margin. Mature leaves have a whitish appearing underside. 
The third maple is the Norway Maple. It's leaf is a simple, dark green, 5 lobbed leaf with sharp points; yellow fall color.
The Norway Maple was introduced in the US in 1756 and is native to Europe. and has been available in nurseries since its introduction into the United States. The Norway Maple is similar to the Sugar Maple except if you break a leaf stem (petiole) on the Norway Maple its sap is milky white where the Sugar Maple's sap is clear. The Norway Maple's keys are also at a sharper angle than the Sugar Maple. The Norway Maple tree's bark is regularly grooved where the Sugar Maple's bark has irregular grooves/plates. 
The fourth maple we found was a Japanese Maple, although I am not certain to it's variety. The leaves are simple, 2 to 5 inches, opposite, with 5 to 9 lobes; green during summer and dark purple in the fall.
The last member of the maple family is the Box Elder, which was covered with Box Elder bugs. The leaves are pinnate, compound and opposite. It looks a little like poison ivy.
The box elder bug is about 1/2-inch long and has black with orange or red markings. Their wings lay flat over their bodies, overlapping each other to form an ‘X’ They do not bite or hurt property but they are are primarily a nuisance because they enter homes and other buildings, often in large numbers.
