CINXE.COM

Just a moment...

<!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=Edge"><meta name="robots" content="noindex,nofollow"><meta name="viewport" content="width=device-width,initial-scale=1"><style>*{box-sizing:border-box;margin:0;padding:0}html{line-height:1.15;-webkit-text-size-adjust:100%;color:#313131;font-family:system-ui,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica Neue,Arial,Noto Sans,sans-serif,Apple Color Emoji,Segoe UI Emoji,Segoe UI Symbol,Noto Color Emoji}body{display:flex;flex-direction:column;height:100vh;min-height:100vh}.main-content{margin:8rem auto;max-width:60rem;padding-left:1.5rem}@media (width <= 720px){.main-content{margin-top:4rem}}.h2{font-size:1.5rem;font-weight:500;line-height:2.25rem}@media (width <= 720px){.h2{font-size:1.25rem;line-height:1.5rem}}#challenge-error-text{background-image:url(data:image/svg+xml;base64,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);background-repeat:no-repeat;background-size:contain;padding-left:34px}@media (prefers-color-scheme:dark){body{background-color:#222;color:#d9d9d9}}</style><meta http-equiv="refresh" content="390"></head><body class="no-js"><div class="main-wrapper" role="main"><div class="main-content"><noscript><div class="h2"><span id="challenge-error-text">Enable JavaScript and cookies to continue</span></div></noscript></div></div><script>(function(){window._cf_chl_opt={cvId: '3',cZone: "www.oecd.org",cType: 'managed',cRay: '912d67735960fdae',cH: 'TI4XNBcVnHWGGQiG0IIRtvPT3XOviCgthORQ9wKajtY-1739707507-1.2.1.1-5PpWYOovTGYVYSCGvawNxbYHfvKMB87xtMGcg6QPNpkwp6WX.EWwnGEW0QCagqIP',cUPMDTk: "\/en\/topics\/learning-environment.html?__cf_chl_tk=A8vWhRXH5Ks2t9nVBLH5gDQuCPY6E8uBNUMzIx9vG8M-1739707507-1.0.1.1-E4YTKIylnsT5QXYnuPG16GU3dArY3q5nlojOwB4Mu6g",cFPWv: 'b',cITimeS: '1739707507',cTTimeMs: '1000',cMTimeMs: '390000',cTplC: 0,cTplV: 5,cTplB: 'cf',cK: "",fa: "\/en\/topics\/learning-environment.html?__cf_chl_f_tk=A8vWhRXH5Ks2t9nVBLH5gDQuCPY6E8uBNUMzIx9vG8M-1739707507-1.0.1.1-E4YTKIylnsT5QXYnuPG16GU3dArY3q5nlojOwB4Mu6g",md: "99ThVTKo934HnQ5Cm5HERfSXJC.gIdTAr7nTSeKXrhA-1739707507-1.2.1.1-jSXrCTlpUB.0MSEzzl5M8BvRoAjO2KkbJFSG2KDjlW_1ftPfyHTUUlpeaPqqSePf1xjI2xbdF8Xu0FWiMhvRmPoGLES8BojaNmmDxVM9PylqprpTQ0wVb9fKTTOclPfwRZF4omFwtw.gYeHHmol9lXb6jkl7GGXGWsiWaxPtw7zNTLJZSMF0fBBLbymsIfEQO2nRDJ3nsgKEJJRXyXhYVpos8ubcDCjX6DzxixdHRFkw7fIonPT7R7EHtWtRWwIqzcSLg9udhxgduPwqrP4Ra9Yzb4wwxx6lo269Fmix7K_SxyQ3BiWUFHHywWatuG5ymiwkzkuid.ET4cLzvZjAfcFMNiGD4huHkbxyrbImRzJwx1h18YM4SapYz6T1n62JJ3eX.8MsbartM0lDMtdJ._CEa8WF07ne7d5wm4tQt7ANVGe.WDalclGeaTYeD07ckChWK73JdrVDbb9P4puuDEO8KImXS0yb7A1w6LXoozYHtt6qApqIwk_eHWolQdZ45d2j2Z1gJSVAS2chQVyIICTRjhyzeAmaWIY7Lsbgde4mkejEW0DcvgAiaL_FY5lRYngTMAbnHSTpxP_Jz23lUwbgvyWETySFBxAX02o9oJGrD1_0aYaiKd8UmIlAu7RzIzOiWZQaCM7_vafcmueb3tXF1iUWjsfzScFIheS3CdKe1.rAKgSp4isKNSH3Zkj67ZoSuMfJWeAjvkV6IhmsQ3oJAgA1HNFIWjVwtnQdqCaCcsFON4dt1zZPbLNdGYZ1lQVeHwZ8dSy2iAE1FLjNX2siIiogmZoOyABygSqG_T7R2924hQ0zorPjbPChhUB05vhwU1WJ8NtfopajlMbo7Lwq51kn0CBAGD.G66.iajavZw915xpbyVJCmDhkGXeOSiD0bkI43oQvaSOpdbovv3ndVwtUQl0De5Z9CzRGRXzetn3rkJLpouKgLcah_nyzK4Li4cCcyndCXWD_Ax0nl6qiKiswtAobdL4UMQ51SHDP0KQNmZcgOU_wT3j4.FV2M2mlQmWMtFqEFmri16Kki4lSHxY_G2gZtD75DLoNGa_8jK6a5zOFyt6yku4AMdL6sssegqmTtNEwI97OtSfhEoiE.eTCaHA0PZzxRJVDD3VyH_teeopIPvHvjug80FvkV8mLL1qxDQOZr3E1lPCifudIFSaquxbHlrgHBTKZCk2FLKhfKSH55sFzYmeIshIX.rDE9VuogOJ2YNsDLzDPxRa1kD._WbD67pQj9cg4QmsEtQuVJpp71uwmp.AwuJbKgZ32hTRdVRBJ4WUB2CMZNVIG12czMQaWo7mNqrDb6bj6_YmXL9WhDProW83jw7TQQvkvddA.EUI.4KWGRLaTqEgTJ6DmEGv7NecsVVvSoJXXOyhQ_C41YFJ4a8llygrglnJF_JewvlAgge6AnyqcbKz9cTOA9EiD3qqRM8X5CNjdcVu.EJ7RZ52n13Yk4jNeUxhzumyHQROMAjNWpFo6PuWLrFsdi63OMiWbIhKte.FNSxGl1kMulOj0uem4pbzsVhtGvyQ586V4F6vS0zs_DVRQzXV1ZDyVzuDOCfl8HnLYUVE3VVIDFMFUxG0Av8CGtJ9SyK2ZDErZEEoYWFZJk0e7ouZeJDETPxKoj.T8wkRFLGMQWqa2HXZvLhl8Yrf9913MucGJQS9n45TxfjMGCt4l4ypWhjM9wIlzR4x0fkWcvMYMqCyGOdi47fXrYzxHtg19DnUES67xsO04JX4ykaIdGHV5PH4ukMFYAQrOLyOysEyGFzY3.BKxQOSKW6oRTQ4NdQuDVyP0K7r2E6sWRIvbI2GukLANnh4yt44ox1VJA1jxD2gIbR1CVOAK3rBrCWNb8OC.ZtauBSjXSkNhlXDlZG61fzn3hDXRnB.AV9_xYb62HrySU7j_3iOSq2Bg302A7l.WZQAsJh5KSvWQuaSrjmUuN.5PxYQAlyBq90XnrYuItuYvaJE4QOmRXJ.aof9vMSfQ5u37IGolnoyjMvps4eK36NJCfjBmw50b0HJjgG6ydpqQYOoRCmGSgxe92on8VT2KyYiLNe8kPLg_guogXr.hDMtqDJNm9Zw_3Z8IE9qxQKI9IMca04FkwlqzfBGQJEMnQ_qhVlUu7D2Y_.SwWbWAGmuiEA4NNTwXz9iXCtsbFH3eg_XXwwgat3gN.JT9.brap_Q4bHDsQvrK0yu1DOIJU6zMQv2Q9o3yDtuMNyHzSdMM4ggm.yhLdFEurQQFXsQzhXH6hxtcugPbxpKV.L9_K5AZnfHgUjUoxaNfQFTytZupbGTxVhYtRANbCZr.6MlsAqOn9d49553_pJv7uCQh8xm2d0IF2LEUcAdv3jSoYeVC5mF_hKcQ_zKRgF7K3e1.DUHPCvrH8BLwy9m7byDVI2ZvVUvrq.VkRK.JoCufB2O9zvbzoDVvdKUr43dWxLo5S5CHU7T_r4IitbvnRKsS1gyJ9qxjRl4MiwKILpEJR2ci_mTjC.JrPgsLQxDaV.tkWygH13MWYku0G1cpMxU3duhaDXNqbWCWCAKRA1eKha9KYlyrGTmnKPfsTINa1EICeaORgf4sjElFVA",mdrd: "YMWZb7adr6M1vYFavK.lZ4aHVDWrkZkvmItv782xo9Q-1739707507-1.2.1.1-Ab3j_8PNvvY_S03dou8lMGXP9yqHtgDT9zT5mniTk7QJb1chIZSAouC5.Iphc9I.NC61dEcjWTbmPRr_BjUOtPbskTYTy1jlT5_iukx5m8_xMoA.8JcLHuFrGqEXVX7AihI0yhpXaBIgSyFqUbymuYtZ2yPJDNGKxYXBsoa_09DRUpKRWDE2JXl85xdbiuDd3vSw.gG291LtkzF7G2q0vFJHk35OBE5ojTRFE4qElEcx7kMyKjpjLPNTtVFAbxcniQyu4ZP3QVSMF0dYWLbVqNTdFPe8L5EDL1qL5Tmd69SGYwEgLlsYUjXADUkH5d6BV7NIrIqGHDvoqNlMq9u_y_RfR.pqHskTwhNl3j1P4iVjddbhiSTPw5Xg2GKV7awmna1JO8YRYgcVltriylFQGjfneIfs7WENIqNe95aOiCizeA4suWEd83q0rhKVFHS96AgS1lwMG.qMB.LVM9dz9ruR7Gpat_6DJzFwsbjXSEgKnKu723VgRvTUrY7js39QF5HIesuXPpORBB4ckXs6B_uuRzODWYHpgyVbd7KEFzaHBiYRGpkhHRjabKM7tZgWYrB29tTveMs5GLXTesKDCPS81NlNjbnvPVX4Mto_LeM_C80sSriFXDOHXVUitlwqcO5DL0Qnn7NNg1DHXNaswV6KyOsC_hME24l4dMjtaaIshYDjVTBVwQ.MH8NXO5xBTzWa7bvmU3P7kC8kF.jd1TYLuwxiKEcxOaAFDrf7vaH0JNKIPL9EmcczsOp94DV6jYXLx8o3uWp9Yd6e5eU1n5s2rnLwe52B7ptjoubsB3E7rxFPp_.qR3QnCjwbzxta2m383ERjNPfHXLb8pURscc96Ft.8VeFg.84z90NPGexz5uEah9fxW33tzbGV1z02wJxQTgBecnAVYEtMH3HHHR.QXhfjZAu5JzItbCkueCDb2oJTKRqK3DpV5RGc2KzOp2n9efhYAyok6P4W6X5fAshuXA6ryodV_JqOrbqkw_GIjSBrjM1muaRbo3L5BVfPQwE74ASpvKN6yljyuqIGg5bqJQPZyZcbAFyWmDv9MyvLt4aKyoitu0EMpuXAk_CHi9BylEXf6jGirJGdC_mE0iwflAwnQS2w6ZZ0gpFKN0210ILtWeJiiJgoIWxzDmvmItHRml05isFjUNkcIyyqk8GU99zKdI5VIa_dZnAbd_sRzyCiOdJhXdFU55BnY.OOWt9Q1BJvDKlEbVT8jc15hpY7RJQLOVidE0_7oIgz6i215jD6gpSflx_X1JbCSuZLdApACMWRcI8R7aSyHZ82PN9ChWBaxRxpeVELsyySRTI54ZxJEo2oibPpNshHqEkhiILhzl0b.GrbzFj0m5e0jmMaNp4Grf2.aoYeB_or5s197eDVFJ476_rV3Kj2g1sDsaRYTK4ibE9AJ5p4BYMsH1t3lYPbWmYI_ujNVNM2YGm8jL0pdFN7K6LNtrz_GBoKXD10g4T2nweklcUs4TUvmoEDOsrhSm3VuSLhu2GFaee_4WmYcaLir4BywudBubZOzW24BBYmwlSZ.GtnBYVGgafXno6q5Dz8oSatQ1GIv5_nnZeO.V_oxLwUvnVBR_BxwAjbjDsBrQKKmPHJO5a3T0fXxy5F7YYxD7Row.W2KQDlK4Xv.IFzaj.djs_SdP6IybOZ8NDhFYYAtR_hrtNlnXlLFe_Kx3acbs3xq4WqFcKTPQSfay9.XbcE07XrFlo6FHolRrkv82CvFzYQTJldxGHrh9ZQfESgbNQusFsCLVgeDl.z1sph3WFx2vdj8kfdTos0ab3G0VxUXbXisDnKEu2R8oec9BlYLBCdCrGEcYKBQRGnwNs3kZ2QEb4GwKR.H0sawhhqzqsiYOSHqmGGug71L8VLjst.2Xb3oazBYowhV9s_HpV4uSYDW_a.ksm68.yCxarSPDq9BTYB4Ruc8AFkuDGsTlwCmpmfh9vv6j4"};var cpo = document.createElement('script');cpo.src = '/cdn-cgi/challenge-platform/h/b/orchestrate/chl_page/v1?ray=912d67735960fdae';window._cf_chl_opt.cOgUHash = location.hash === '' && location.href.indexOf('#') !== -1 ? '#' : location.hash;window._cf_chl_opt.cOgUQuery = location.search === '' && location.href.slice(0, location.href.length - window._cf_chl_opt.cOgUHash.length).indexOf('?') !== -1 ? '?' : location.search;if (window.history && window.history.replaceState) {var ogU = location.pathname + window._cf_chl_opt.cOgUQuery + window._cf_chl_opt.cOgUHash;history.replaceState(null, null, "\/en\/topics\/learning-environment.html?__cf_chl_rt_tk=A8vWhRXH5Ks2t9nVBLH5gDQuCPY6E8uBNUMzIx9vG8M-1739707507-1.0.1.1-E4YTKIylnsT5QXYnuPG16GU3dArY3q5nlojOwB4Mu6g" + window._cf_chl_opt.cOgUHash);cpo.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(cpo);}());</script></body></html>