INTRODUCTION
The goal of this study was to identify the “working instructional ingredients” when students acquire knowledge in small groups. The main ideas were that learning benefits from (a) active engagement, (b) collaboration, and (c) student-directed learning.

STUDY GROUPS DESIGN
We distinguished four instructional design dimensions:
1. Procedures;
2. Collaboration;
3. Tutor- student relation;
4. Assessment.
With these instructional dimensions, we describe 17 ingredients of our small groups:

The procedural dimension
1. In the small groups, students worked intensively, during a short period of only 5 weeks, and with 2-weekly meetings of about 1.5 hour.
2. All the weekly study activities were put into a ‘structured format’.
3. A plenary starting meeting was organized (a) to clarify what students needed to learn, and (b) to motivate the students.
4. The study groups were voluntary and presented as ‘exclusively for motivated students ’.

The collaborative dimension
5. The average size of our student groups was about 7 - 8 students. We formed three study groups.
6. The peer students in the small study groups provided explanations to each other.
7. We created a ‘social control’ situation to stimulate students to work.
8. We designed a similar situation for all students, to create a feeling of group cohesion to stimulate students in their work.
9. Students had to commit themselves to the program; if they did not respect the requirements they could be excluded.

The tutor - student relation
10. We used senior students as guiding tutors.
11. Learning was directed towards students needs; students choose the discussion problems.
12. The tutors registered the home preparations of the students.
13. The tutors also registered student’s attendance and participation.

The assessment and feedback dimension
14. Students were in the first meeting confronted with positive study experiences.
15. We did not provide solutions to exercises only after students had made exercises themselves.
16. The final course assessment was ‘very rapidly visible’: after five weeks.
17. If students would fail for the final exam, they could not automatically do a re-sit, but had to apply for a new exam.

METHOD
Participants were 24 senior university students (academic year 2007-2008). From the 24 participants, The 21 students that passed the course, together with 20 architectural staff members filled out a questionnaire to find out whether the 17 instructional elements ‘had contributed in a positive way to learning’.

RESULTS
Both students and staff members agreed on 7 elements as working ingredients:
1. The structured format of the study-groups;
2. Exchange of knowledge with peer students;
3. The coaching and 4. the feedback of the tutors;
5. Positive learning experiences in an early stage;
6. Education directed at student needs;
7. Social relations with other students.

Next, and in contrast to staff members, students were less positive on the benefits of 6 (extrinsic) elements:
1. The monitoring of students’ preparation;
2. The monitoring of attendance and group participation;
3. The starting meeting;
4. Threat of exclusion for the course;
5. Threat of exclusion for a future exam re-sit;
6. Social control by peer students.

This is result indicates that intrinsic measures have more impact on learning than extrinsic measures and provides suggestions for future small group design.