Climate change is a threat whose mitigation can be enhanced by collective environmental protest behavior, so understanding the motivation for collective environmental protests is important. A questionnaire study was conducted among 454 young members of Fridays For Future WhatsApp® groups in Germany to assess whether the frequency of their participation in Fridays For Future events was predicted by identification with the group (social identity), or the individual factors of environmental self-identity, activist self-identity, altruistic, biospheric, egoistic, and hedonic values. An ordinal regression showed that social identity and activist self-identity positively predicted participation in environmental protests, but environmental identity and biospheric values did not. Those who reported higher egoistic values were less frequent protestors. Our results suggest that identifying with the FFF group, and personally identifying as an activist, could be more important motivators of collective environmental behavior than self-identifying as pro-environmental, or than environmental values.