What kind of camera works best for the PLOTS balloon and kite activites?

You will need a camera that can do continuous shooting (or "continuous drive")
<img src="https://publiclab.org/sites/default/files/continuous_0.JPG" width="500" </a>
<a href="http://publiclaboratory.org/wiki/timelapse-apps">there are apps for iPhone and Android</a>.  See if your camera is on this <a href="http://www.dpreview.com/products/search/cameras#criterias=SpecsCoreParams%2CSpecsContinuousDrive&includeDiscontinued=No&sort=newestFirst&view=list&page=1&paramSpecsCoreParamsBodyType=UltraCompact%2CCompact%2CSLRLike%2CLargeSensorCompact%2CRangefinder%2CMirrorless%2CCompactSLR%2CMidSizeSLR%2CLargeSLR&paramSpecsContinuousDrive=Yes">list of continuous drive cameras at Digital Photography Review.</a>