Step one: Draw a picture on the black board. Then add dashes underneath for letters. If the students get a letter right, put it on the appropriate dash. If they get it wrong, write it down a "wrong" section. If the students or team gets a letter wrong, they lose part of their snowman or a mushroom.
Slide 1: One snowman. The whole class can work together on this one. Good for quick warm-ups or cool-downs for the end of class.
Slide 2: Divide the class into four teams. Can be used with whiteboards, or the teams can say the letter they think one team at a time. If the students get a letter right, they're safe. If they get a letter wrong, they lose a snowman part (cap, eye, nose, then body circles). Just click on a part to make it disappear. Clicking the eyes and cap can be tricky because they're so close together, so just watch out for that. Better for classes of 20 to 24 students or less.
Slide 3: The "Super Mario Bros. Edition" of the spelling game!! I have some large-ish classes (between 33 and 40 students), so I made this to make teams sizes more managable (3 to 5 members). Best played with white boards and / or colored cards (something I have for team games). If the students get a letter right, they're safe. If they get a letter wrong, they lose a mushroom. Just click on a mushroom to make it disappear. This variation would be good for 6th graders and junior high school students.
This can be used with high school students too if you just want or need something fun to do for a few minutes.