NOTE
I haven't updated or used this activity in awhile. If you are going to use it you should take a good look first for dated cultural references and stuff that doesn't suit the new teacher strategies. If nothing else I hope these older materials will give you some ideas for your own materials.
NEW VERSION
I've added a new version to be used with Let's Try One, lesson three. It uses the vocabulary from that unit. It also has number practice. Its meant to be used over two lessons. The first lesson practices 1-10 and the second 11-20. On the number practice pages if you click the number a star appears. You can click the star to make it vanish. This is to be used for substitution drills (Such as clapping rather than saying a number if there is a star) or Eraser Grab Game (when the teacher says the number with the star students should try to grab their erasers).
The memory challenges work the same as the original version.
There are three stages to this activity.
Part One practices the vocabulary in single form. Click on the start button once to make the images appear and then after a few seconds click again to make them vanish. Then have students raise their hands and say what there was. I usually have them say 'I see a ....' This can be in groups or individually. If you use the answer sheet you can click on the correct number to reveal their answer.
Part Two has 8 questions.
I generally have them make groups, then show the image and have one member of each group race to a teacher with their answer.
Part Three has two rounds and a demonstrate round.
I do the demonstration first. Click the start button once and let them see the image for a few seconds. Then click on the question button to reveal the question. Do one or two questions to get the idea.
When I do the real rounds I usually let them see the images twice. Once quickly and then a second time for a bit longer.
NOTES
You can use this link to see a presentation that can help with editing my activities and making your own.
https://www.altopedia.net/activities/866-how-to-make-a-powerpoint-point-game