In line with previous studies, where outdoor nature experience was shown to support adolescents' environmental knowledge, our study monitored the influence of a hands-on environmental programme within a National Park on cognitive knowledge achievement. A sample of 4th and 5th graders (n = 289) completed a week-long outreach conservation programme with two follow-up options: the first group (n = 170) interacted with thematic posters, the second group (n = 128) also completed a thematic board game. In a quasi-experimental design, we analysed both versions with regard to achievement efforts and individual situational emotions. Altogether, programme participation added cognitive knowledge, while group one (poster and board game as follow-up option) outmatched group two (just the poster option). Measures of "state" and "situational" emotions regarding the programme and right after game participation revealed positive effects toward knowledge. Thus, we conclude, direct experiences with nature and additional hands-on follow-up activities may foster a student's cognitive achievement in such programmes.