Case study
CLL
Language Training, Community, TikTok, Meta Ads, Google Ads, Belgium, Native Content
By taking over CLL's complete digital strategy, Socialsky transformed a fragile online presence into a true engine of brand awareness and performance: over one million views on TikTok, a signature format that generates 191,000 views and 9,310 interactions on its own, and Ads campaigns whose ROI was tripled - for Belgium's number 1 language school.
Context
CLL (Language Center), founded in 1984 by UCLouvain, is Belgium's number 1 language training organization. With 40 years of experience, it offers 29 languages to individuals (children, teenagers and adults) as well as to companies and public institutions, through its centers in Louvain-la-Neuve and Brussels, and its online platform CLL Visio. In February 2025, Socialsky takes over the TikTok strategy. The collaboration then extends to Meta management and advertising campaigns (Meta Ads and Google Ads) from August 2025 onwards.
Challenge
In the language training sector, social networks are rarely seen as a strategic lever. The stakes were multiple:
- Starting over from a weakened account with signs of follower buying and almost no engagement
- Deconstruct the "language lessons = boring" image to make CLL desirable
- Build an organic community in French-speaking Belgium
- Maximize the ROI of Ads campaigns on constrained budgets
Solution
Socialsky built CLL's TikTok strategy around a central principle: make language learning fun, accessible and rooted in Belgian reality - without ever sounding like an advertisement.
Key approaches
- Creative Lab: Testing multiple creative angles in parallel to identify high-performing formats before scaling
- Signature format "Street Interviews": Spontaneous interviews ("5 words in Dutch", "Test your Dutch level") that became a growth engine
- Two complementary pillars: Street Interviews (native content) and Adapted Trends (trend hijacking) to alternate between engagement and virality
- Ads optimization: Restructuring of Meta and Google Ads campaigns with more qualified audiences
Results
In just a few months of collaboration, CLL established itself as a reference on TikTok in the language training sector in Belgium. Winning formats include the "5 words in Dutch" Street Interview with 191,000 views and 9,310 interactions, the Bad Bunny Trend with 219,000 views and 31% retention, and "Expressions BE vs FR" with 118,000 views and 515 new followers. On the Ads strategy, Meta Ads saw its budget reduced by 60% while increasing conversions by 19%, with cost per conversion divided by 3. Google Ads multiplied its CTR by 6 and increased Impression Share by 84%.
1M+
Total TikTok views
191K
Signature format - Views
÷ 3 (€67 → €22)
Meta Ads - Cost reduction per conversion
6x (+518%)
Google Ads - CTR multiplied by
+802
New followers in 1 month