Evaluation tool 8 – Pebbles in a jar
What is this tool?
Dropping pebbles in a jar or box is quick, easy, and highly visual, and also provides an opportunity to participate for people who may find reading challenging.
What kind of activities can I evaluate with it?
This tool is particularly effective for use with general public and schools audiences at drop-in events (demonstrations, festivals etc) and interactive workshops, but can also be used with interested adults and at ongoing events (courses, astronomy clubs) and lectures / presentations.
Pebbles in a jar at a glance…
When should I use it?
This tool is best suited to use at the end of (or after) an event.
What do I need?
- Pre-prepared container, for example a box, jar or chart.
- “Votes”, for example pebbles, tokens or stickers
Let’s get started…
Ask participants to provide a simple visual vote on a topic relating to the activity. Hand out your “votes” (usually one token or pebble per audience member) and ask them to place it in the box/jar or on the chart according to their opinion on the question asked. This usually works best if you have the question clearly displayed near the container, as well as mentioning it in person during the session so people are prepared.
OK, what do I do with my data now?
The beauty of this technique is that it’s so simple to analyse. For many situations all you have to do is visually compare the levels of ‘tokens’ placed within the different boxes/jars. If you want to be a little more specific you can count the votes in each category, thereby allowing a more quantitative result.
This technique usually works best for questions related to attitudes or emotions, i.e. how people feel about or reacted to the event or its content. This broad view of the participant experiences can allow you to identify whether your activity is achieving what you intended, and photos of the final votes can be used for reporting purposes.
There are many variations on this technique, for example:
- If you place two containers near the entrance/ exit then separate votes can be taken: once as participants enter, and then again as they leave the event, to give you an indication as to whether any change has occurred. Be sure to indicate clearly which container is for use at the start and which at the end of their participation, and to keep the response options consistent so that you can compare the before and after votes. Or you could use different coloured tokens in the same container(s) to track the votes before and after the event.
- Have multiple option slots in your container, so that participants vote from amongst a variety of possible options. For example, you could have a statement like:
I want to follow a career in space science then have options of Strongly agree, Agree, Neutral, Disagree, Strongly disagree for people to choose from, thus helping to judge participants’ strength of feeling on the topic (rather than just a straight yes/no answer).
- Have multiple response options, such as different coloured stickers. For example, at the end of a series of sessions for an astronomy club a large sheet of paper could be set up and divided into the different sessions or areas of content covered. Participants could be asked to place different coloured stickers on the various sessions according to different knowledge or emotional reactions (Figure 1). Note that it is important to have a clear key, and to ensure each person only gets one of each colour sticker in order to avoid confusion! You can also invite people to write on the paper near their sticker to explain their vote, thereby providing slightly more in-depth information.
WARNING!! If using sticker-dot voting do be aware that there are some limitations – http://dotmocracy.org/dot-voting/ has some great advice on how to overcome many of them.
For younger children, use jars or plastic cups with options clearly written on them. Give each child a token (e.g. a piece of pasta or coloured card) to put in the jar that represents their preferred choice.
- It’s usually best to cover the sides of the jars or plastic cups so that the children can’t see others’ responses. This means the children are more likely to think for themselves, instead of putting their token in the most popular option.
- For older audiences, use large see-through jars: many participants like seeing how their own response compares to others, and feeling “part of” the event in this way.
Download the Pebbles in a jar tool worksheet.
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